Cod 4 or Black ops are probably the two best. Guns were more balanced for Cod4. Best game for competitive was BOPs2
Also sniping in Black ops requires more skill than any other cod.
Pretty much agree with all of this.
COD 4 had such a good mix of everything. Since I play Hardcore, OP guns don't really exist but COD4 had a lot of good guns you could use.
Black Ops 1's sniping is almost all quick scope. For a long time I would use the FN Fal for a type of sniping, but it's have the acog, so not REALLY sniping. In Array I'd use the Thermal Scope but it was still hard. There isn't a lot of opportunity for sniping in Black Ops 1 so you really do have to be a quick scoper to have any success, and I never understood how anyone quick scopes tbh.
Black Ops 2, for me, isn't good enough to play without an objective. The levels weren't strong enough. Black Ops 1 and COD 4 have some fairly great levels which everyone can enjoy in TDM, but Black Ops 2 didnt. Capture the Flag was brilliant for me. Me and my mate had like a strike team. We'd know the quickest routes to get into the enemies base, knowing how to watch each other's backs. We'd know the best places to drop Tac Incersions, so we were almost like parasites in the base. He'd take the flag, I'd stay in their base. If he drops or captures, I'm sitting right there to take it straight back. If he dies, he's straight back in the base again. Points were amazing. My class in that game was cool too cause everything was about speed. I took off everything except the burst fire handgun and would use it.
In Black Ops 1, everything is about getting high up on the weekly ranks, and getting my ratio up. I was #2 in the world last week but that's cause #1 was hacking. My ratio is currently at 2.82.