Getting some Left 4 Dead achievements!!

Hi there!!

Atm, im 5 short of getting the full 50 achievements and that sweet sweet 1000 Gamerscore!!

just wanting to know who is up for gettin:

What are you trying to Prove?

Stomach Upset

Nothing Special

Zombie Genocidest

Red Mist

I can get the last two with just more and more playing. But im tryin to find some good players to get the 1st 3.

If anyone is interested im playin tonight, add my gamertag : Gregson616