From my experience in mw2, sometimes a sniper is unstoppable.
Take the map Terminal, for example. The team that eventually spawns from point A (boarding zone for the plane) can be permanently pinned down by two snipers with Berret .50 cals and stopping power, and One Man Army for infinite ammo, while the snipers' team fights from the flank. The team at A is killed instantly if trying to enter the plane or go down the adjacent walkway due to 1-shot kills from two snipers. The third path is a deathtrap waith atleast five enemies at any time. You cant kill the snipers because you are killed as soon as you can target them, if not before. Even noobtubing fails. When one sniper stopps shooting, it's only to send harriers, choopers, or an AC130 to spawnkill team A for a minute.
Counter-sniping tactics, my ass. The best I can do is destroy their killstreaks with stinger missiles, and try to spot the from a flank with a thermal scope on my M16. And on this map, and several others, all anyone can do is die 20+ times, or leave.
It just doesn't matter what weapon you have if you die before getting off a killing shot.
Sorry, but I've got to ban you for playing MW2 if you still do. The only mildly satisfying experience I had on it was the story (which was still not as good as the original MW) and the Spec Ops (which was actually pretty good). My playtime is 15 hours SP and 5 hours MP. Compare that to the many gamers with 24-hour-plus MP times. I don't know if I have a higher average "quality of game", have a wierd sense of what a "good" game is, or if MW2 was just plain bad compared to most PC games, but I just didn't think it was that good. Unbalanced, that's the word I would use for the multiplayer. It's like MW but with too many unbalancing complications. And for some reason, everybody at my schoiol thinks running around with a rapid-fire shotgun on a small map is "skill." I think it's no better than noobtubing, if not worse, because at least you aim with a grenade launcher.
