You might as well be playing those some no budget cs clones because they run p2p as well (no dedicated servers), so the lag issues are going to be the same. There's no way in hell you are going to accurately snipe someone when your ping is like 90 and theirs is like 150+.
Whenever I have to worry about if the reason I died was because the person was better than me, or their ping was just too high (or vice versa), it's frustrating and hard to play.
Also, I'd like to point out that Crysis/Far Cry 2 still looks better MW2.
I'm not really complaining about the single player (though I don't like it personally).
I'm just saying I wouldn't buy this game for PC when there are better alternatives, and the game was clearly made for consoles. Why not just play it the way it was intended?