I'm only a little ways into the game but I very much like the Shredder and the Bull. I'm not as much of a fan of the signature sniper rifle. I'd much rather have a suppressor because of how I use the sniper rifle.
Basically right now I always carry the Bull, the Shredder, and a silenced M-700 (w/ the high power scope). My 4th weapons usually depends on what I'm working on in the game at the time.
Awesome pic provided by Dirty130