I actually don't.. it seems pretty douchey. However, when I get killed first, I'll spawnkill that motherf*cker 10 to 20 times at least. If it's a low level (1 to 30) I'll kill him 3 or 4 times, it feels kind of abusive if I kill them more times.
The only times I'll shoot some f*cking idiot first, it's if they're being annoying on the mic and If a higher level it's griefing a Low level.
Nothing pisses me off more than being shot when I did nothing to deserve it.