when i used it during my path to getting getting diamond, that was the one that i gave me the biggeset headache. it seemed to have taken a lot of bullets to kill an enemy and my accuracy isnt horrible either...it was decent enough when i used it for a while but it was my least favorite of the smg's
the pdw will probablys be your best bet with it having a 50 round mag but I'd also try the vector it's a great little gun that I hardly see anyone use
I like the Vector a lot as well. TBH, there's not really a gun I don't like in this game although I don't snipe or use LMG other than what I pickup randomly so can't really comment there. They all have their strengths and weaknesses.