I haven't really had that issue and I go in by myself most of the time. In Halo 3 I felt like it was mostly cheaters at the higher level like people who host boot. Then again my brother played Halo 3 more than I did. In Reach for the most part if someone quits it's like "oh shit I gotta go sorry guys" and not "you guys are garbage so I'm quitting" However I haven't played Reach in few weeks.