DOn't try to do it in Team Doubles, you'll only find lagswitchers, hackers, second accounters etc...
If you have a strong team, do it in Team SLayer or Squad Battle.
If you're fairly good with the BR try to do it in Team Swat (even if you have only one teammate you could win, but it's full of trash you can have in your team).
Team SNipers is full of aimbotters.
MLG, don't even think of that LOL.
Lone Wolves if you can't rely on any teammate, and like to do it in your own, but it's a little difficult.
[Edited on 08.22.2010 10:46 AM PDT]