I can quickscopes 6/10 times with the PSG1 and or L96A1. No matter the game the first weapon I always play with is the sniper rifle. I rarely use the ACOG and always use the Variable Scope. It takes practice but for some reason quickscoping is almost natural in Black Ops for me, where as MW2 I had difficulty. Which is quite ironic considering Treyarch did "everything they could" to eliminate quickscoping.
As far as rifle goes, PSG1 all the way. =]
Now I will say this, I think they should have replaced the Reflex Sight with Variable Scopes on assault rifles. Here's why: 1) Reflex is absolutely no different from red dot, and looks ugly as fuck. 2) Variable scopes on FAL and M14 = GODLIKE, and it wouldn't be overpowered because the guns themselves wouldn't cause enough damage to one hit, and if you used anything fully auto, once you get into the second and final stage of your scope, recoil is REALLY going to add up, so you have to burst fire if anything. Obviously if they switched this up, the scope power would have to go from x6-x10-x12, to x4-x6-x10 or some other variation to keep it from becoming a complete camp fest.
"Only the dead have seen the end of war." - Plato
"War doesn't determine who is right.. only who is left."