The other Iron Man
I don't have any recent Hero Factory models so I don't know how these compare with them, although I suspect many of the parts are the same. However I do have one of the Ben 10 maxi-figs and I can say that this is far, far better than those, both in terms of parts quality and quantity, and the actual build.
I think this is a pretty good representation of Iron Man, given the parts available. The big, bad, kick-ass weapon on his shoulder is pretty good, too.
I'm not sure I'll go so far as recommending this set, but if you're a fan of these big figures you will like this one.