I play on PC, my favorite setup is the following:
UMP45 Silenced
SPAS-12 Grip or M93 Raffica Silenced
Semtex
Flash Grenades
Marathon Pro (sometimes Sleight of Hand Pro)
Cold Blooded Pro (sometimes Hardline Pro)
Ninja Pro
I agree with you New_Shine. Camping sucks and run n gun is the way to go. People are always complaining about campers... I don't understand. They're easier to shoot in the head or sneak up on if they stay in one spot!
I run with
Ump 45 silenced
Spas 12 Extended mags or grip
flash bang
Semtex
Marathon pro
Stopping power pro
Ninja pro
killstreaks 7, 11, 25
or killstreaks 5 7 9 (pred, harrier, pavelow)
people never expect people to be rushing all the time, and i can spawn trap one person and kill him over and over till i get my 7 killstreak. gotta love the fail spawn system on demolition... so easy to get nukes