I havnt commented on any post/thread in the past few months, but I really couldn't resist Meph's input to this thread...
I mean he is absulate brilliant in his work for the past decade and the only admin who listen to all of our concerns, also he is totally right to what he said, when giving differences to different weapons.
Personally I'll say stick with the M4 if you like to spar and have a decent spread affect.