I play hardcore in MW2 too, it's just more fun. I like using SMGs and shit.
People say the AK is OP in MW2, but I hardly see anyone use it, let alone get a few kills from it due to the recoil.
But I think that not all the guns are OP. It's just that some people are really good with them, and they make it seem like it's OP.
From my experience, the guns people say are OP aren't really for me. It just doesn't feel like it for me
I may be wrong or whatever.
It's just my opinion.