I spent 2 hours playing with a set, normally, I just build a set, see what is can do, then put on my shelf for display. I DEFINITELY recommend this set.

Building Exp.

There is a great usage of parts to create angles that aren't normally used in technic sets. The pneumatics are a brand new way of saying,"Hey, look what LEGO can do!" However, the best part of this set is how complex the steering system is, it is nothing like the every-day LEGO steering.

Parts

There are a reasonable amount of stickers, which is good, but the parts are where it's at. This set has a new type of bucket, pneumatic lift arms, and a few of other parts. This set even has a exclusive printed Mercedes-Benz piece.

Playability

This set has around 13 different functions which work well when playing with the set, everything responds correctly. Don't worry, it's pretty robust, so that when kids kick it, ram it, but don't go ahead and throw it or step on it, that's just really stupid.

Value

What I consider good pricing is 10 cents price for part ratio, but this set does even better with only 8 cents p/p plus all the cool parts. Overall, I say this is great.

Cautions

Cats really like to chew on the tubes, so keep this set on a high shelf where you know your cat won't get to it. Letting your feline consume a tube may lead to choking or the demise of the feline.

The Arocs!

approx 4.5 kg of Lego bricks :-) The instructions are 800+ pages and 2.8k bricks want to be in the correct place.

Building it was quite fun, the 6-cyclinder enginge (straight in a row) the gear-boxes for the deferential and the 4 wheel steering. Nice and straight foreward, the only tricky part is the big gearbox under he pneumatic powered arm. You turn it around quite often and it is easy to miss it once. So I ended up with 3 gears not build in, first I thought, a few spares, nice.

But after I finished all moving parts inserted the still clunky battery-box (hello Lego? any cool new stuff build on some more environment friendly rechargeable technology in the works?) I saw that there are no spares for the gears. Well you should not build late in the night, I got it :-)

I undid a few bricks after I was finish with the whole model and rebuild the gearbox from scratch. That took about 30 minutes.

The rest is fun to build, the nice details like the grill in front of the drivers-cabin (that you can move up and tilt, to see the engine working) the printed Mercedes-logo on the brick in front of the grill. Only one thing, that is probably not only annoying me, you get a lot of stickers.

The arm with all the flexible pneumatic-pipes is sometimes a bit tricky to build and to follow in the instructions, especially since the pipes are not exactly the sice as written, so measure them and decide what is closet to instruction. and in the base-gear you have to squece a lot of plumbing thru, so take your time there and see how it fits best.

The functions are mostly powered by one engine, the turning of the arm is sometimes a bit too fast for my taste, but it has only one speed, so... the pneumatic has come a long way, but I guess a airtank would be a cool feature in the future, this little pump is combined with the motor makes quite a noise. But overall the legs to stabilize are powered by the motor as well as the linear-motor for the fright-compartment.

Manual powred are the stamps at the stabiliser legs, the steering, the locking mechanism of the compartment (that by the way is very nice to build), and the doors as well as the cabin.

Overall it is a big model, fun to play with, nice to build and a lot of details and functions. I guess it will be a shiny star in every Lego-collection.

Further to the exemplary reviews others have posted I just thought of adding that unlike current Lego builds, which come in numbered bags and you build sections of a model per bag, this set, while it all comes in numbered bags, doesn't allow for modular building...essentially, its like 'old Lego' or 'Old Technic'...you have to unpack EVERYTHING and sift labouriously through ALL the components to build this set...I wondered if this was done on purpose to entail a more classically challenging Technic build or Lego simply missed the point...

I am currently building my set and do find it laboured. I wish Lego had put the correct components per section of the build in numbered bags.

The 2015 Flagship, the Lego Technic Mercedes-Benz Arocs 3245 has been met with many a superlative - but does it earn them?

The other reviews cover the facts of this set very well, so I'm setting this one out a little differently. This review is for those of you thinking "Is it really worth my money?" The answer, by the way, is a resounding Yes!

Parts

There are plenty of surprises in this set. The new Linear booms are very solid and I can think of a tonne of uses for them, from fire ladders in lego city sets to extending space ship legs and plain old linear actuators for larger Technic MOC's. There's the pneumatics, which form a full fledged 4 way system, meaning you can build excavator arms, cranes, and all manner of other functional machines. There are plenty of gears and a multitude of lift arms and 12 wheels along with suspension parts. In short, this is a Lego technic collection in a single box. It's nice that other than the new booms, this model doesn't rely on a host of new or specialist parts. The Pneumatics are an evolution, and almost every other part is just innovative in its use.

The build

The build is epic. Very memorable, and really exciting as the model comes together in big chunks. One tip is to build Stages 5 and 6 first, then 1-4 in order. In this manner, the set comes together very quickly at the end, with no 'boring' cosmetic finishing sections. Once you're into the meat of the chassis build, the technical innovation never stops. I promise you you will say to yourself 'wow that's clever' at least a dozen times. That's about once an hour. Perhaps more! The gearbox is not as complex as 42009's, but it's all the more impressive for being compact and containing both the pneumatic pump and stabiliser legs.

The completed model

It's not that everything works, which is impressive enough as it is. It's not that it looks good, which it really does. It's that everything works well and by aping real mechanical design principles too. The model sits so well as a whole and feels like a functional machine, not a toy or a display piece. The suspension is functional but firm enough to support the weight, which is substantial. it's my favorite part of this model because it's lifelike and really very innovative. The Arm moves realistically due to the pneumatic pump. I've seen people complain about it dropping too suddenly - well, with some finesse on the switch you can bleed pressure gradually creating very precise and lifelike movement. My bucket grabber works well, so I'd suggest particular attention to the bushings and working the piston prior to assembling it. It's just brilliant fun to look at, try out, play with and 'drive' along the floor. My son, nearly 4, absolutely loves grabbing his duplo bricks with it. The Crane arm is free to rotate when not powered, making playing even more fun since there's no worry about breaking anything.

Overall opinion

If you are even half thinking about buying this set, just do it. You will NOT be disappointed. I had to wait 3 weeks to build it, and whilst it sat in the box I was worried that I'd spent so much. As soon as that compelling build began, all doubts vanished. That so many parts, so much detail, and so many functions have been crammed into such a great looking set is frankly incredible. About half way through, I was convinced of it's value and it started to feel cheap for what it offered! This is the current pinnacle of Technic Lego, a statement of intent from The Lego Group and no doubt from Kossmann himself. It will take quite something to top this set in future. A well deserved 5 star Flagship set.

Box

This set comes in a huge box, slightly bigger thicker than the Unimog box, and almost as thick as the big Duplo train set. It is fully packed with numbered bags for the 6 phases of building.

Instructions

The book is nice and thick. The instruction method does not match the age suggestion though. My 5 year old can build it with the book. That is in some way a positive thing, but for an older person it is pretty frustrating. Recommendations for LEGO:

• Make 1 part-list for the whole spread: parts for all steps on two pages can be collected at once. Old technic instructions do this perfectly!
• Make more use of repetition. You often build 2 or more times the same, or ALMOST the same. Combine these repetitive steps in shorter instructions.
• Also don't be afraid to say step 1 and step 2 are mirrored. I really like to built two mirrored parts at the same time. I understand you write out both, but you could make a warning like: step 5-8 on the next page are the mirrored steps of 1-4 on this page. Hey, we are 11 years and older! We know what "mirrored" means!

Parts

With a huge collection of parts I always start with a calculation: what do the missing parts needed for a new model cost separate on Bricklink? In this case it would be close to the purchasing price, so that means purchasing the whole thing for me!
Things that are worthy:

The new pneumatics:

• 1 1x11 yellow cylinder, and very odd: 2 2x10.8 cylinders. Yes, those big ones are just 1mm shorter than 11 studs! In the extracted position the length difference is about 2.5 mm. So the thin one is 11 studs/17 studs, the thick one is 10.8 studs/16.6 studs.
• The tubes are modular now. With many previous models all tubes are cut to the needed length. Here there are many lengths used more than once. The longest routes are implemented by a series of connected standard size tubes! So you will get MANY tubes up to 28cm, but not very long ones as with the Unimog (64cm!).
• This means there are a lot of cross-axle tube connectors, this time 13! in dark grey instead of 2 in blue at the Unimog.

Other parts:

• Then there are 12 wheels. The first time LEGO makes a truck with a double rear axle with 4 tires each and double front axles. There was never a model with 12 of these wheels!
• There is a whole lot of light grey panels and shells. A pity LEGO did not introduce dark grey shells as it would have been a logic choice on the cabin.
• The new gear rack system: it is cool to see it double as an outrigger and as a crane extension. I think the rack is hard to use for other purposes, but the toothed bar looks very useful for other projects.
• A good selection of white panels and wings.
• A great set of suspension parts: 8 dampers, many H-bars, 2 differentials, 10 mini suspension arms
• A massive selection of basic parts, great to start a Technic collection

The build

The build is awesome! Not much repetition, often a sense of "what the heck is this going to be", I like the creative use of parts for other things. For example the steering mech is really wacko! The suspension on the back is also a great example of out-of-the-box use of parts. That makes creative! Nice!

For the building experience I always prefer one-motor-does all with a zillion gears than the no-gears many motors approach used for the Volvo loader last year. The mechanical aspect is very complex and makes the build process first class.

The crane is not at all hard to make. LEGO did a real great job with the colour-coded tube guides at the bottom, the tube-segments. The result is a really easy to fill shaft with tubes, that rotates very smooth. So far the "hardest" part is much easier than I thought it would be.

But then starts the frustration. Putting the crane ON the truck is awkward. The tubes pop out on the bottom, they touch underlaying gears, the frame with the pneumatic switches gets deformed when connecting it to the chassis…. Where the crane rotates very smooth as separate item, it often makes the white coupling gear slip when in place.

Another really hard thing is the mounting of the cabin. The instruction manual is very unclear on this. There are 4 red pins. The 2 that pop into the ends of the grey bars along the engine are straightforward, but the 2 on the black 5M arms have to be put in the middle of the 3 hole side of 2 dark grey 3x5 L shaped arms just behind the 2 red pins you mounted before.

The completed model

The truck looks amazing. I really like the colour scheme. Black with accents is always good for me. To me the mud guards are OK, but the spacing between the front wheels feels a bit too long. No big deal. The cabin is amazingly detailed, with 4 mirrors including dead angle ones, nice doors that open, a very well done grill and nice use of little white wings as aerodynamic shields on the corners of the cabin. The battery box is nicely hidden in the cabin.

Playability is similar to the Unimog, which means most of the same errors are made:

• If you don't make reverse part of the gear box, then include a direction switch with the battery box. The battery box is a flawed design, and not suitable for changing directions. I wonder if it would be possible to do it with 4 handles instead of 2, and have all the handles except the pneumatic pump activator include 2 directions.
• The layout of the pneumatic switches is awkward. The big cylinders should be on one side, the extension and bucket on the other side. Now you make many operation errors. We found it easier to swap the tubes on the arm between the extension cylinder and the second big one. Then you can operate the bottom part on one side, and the scoop and extension on the other side.
• The crane arm is too heavy. I wonder if you can make it with half the parts. I would accept the crane to be more flimsy if the number of parts would have been reduced greatly. Only when the pressure is almost at the maximum, the crane will get up.
• The mini-pneumatic-cylinder for the scoop is not up to the job, just as with the Unimog gripper. A classic big one would have been better.
• Rotation of the crane is best decoupled from the gear-box by removing one gear, and make it operate by hand.
• You would expect the coupling gear to prevent ticking of the linear actuator that operates the bucket, but it does not.

Note:

When you use the pneumatic switches with smaller divergence, it will be much easier to operate the crane. For example you can slowly lower the whole crane, where it usually drops down immediately when you switch the lever all the way. Another benefit is that the cylinder remains under pressure, and that it goes up directly after if you reverse the switch. With normal use the pump has to build up full pressure, and that takes 10-15 seconds or so before the arm goes up.

Overall opinion

The Mercedes Arocs is an amazing set. The greatest features are the awesome pneumatics part collection and the awesome building process. The new pneumatics make the range of the crane excellent for the first time. You can reach everywhere in the bucket and around the truck. The aspect ratio (width-length) of the cylinders is very nice, and give a very nice "hydraulic" look.
I would recommend the truck to anyone who likes to start with Technic: you get lots of everything at a sharp price. The truck is 50€ cheaper than the 42030 Volvo wheel loader, yet way cooler with 1200 extra parts in a much greater variation of colour!

An instant classic!