Here is the basics of some fo the reports I have recieved.. Player A is on a server playing just fine for over an hour. No warp, no lag. Player A gets owned several times by Player B. Player A departs the server, returns in a few minutes, has the same ping but now warps and is twice as hard to kill.
If I had been told this from one source I would shrug it off, but I have been told about such behavior on 5 different occassions and by three people I know to be trust worthy.
While low MB is a fact of life for some players, if a player adjusts their setting to give themselves an advantage over other players then I have an issue with it.