User blog comment:The Gunsmith/So, what weapons did you actually end up using?/@comment-1503545-20120417134620/@comment-1388547-20120418051401

I find the Katana pretty decent at point blank (Vanguard), but its biggest strength is in multiplayer where it's the easiest shotgun to get to upgrade level X. At equal upgrade levels, I prefer the Eviscerator. The Carnifex actually works really well for me with a scope on it -- at that point, it's almost a handheld sniper rifle, with much less weight than a full-up sniper rifle.

I wasn't too impressed with the Particle Beam either, but if you're playing a damage-dealing class, it can have an unexpected use in single-player: the beam acts as a target designator, helping you find the next enemy to kill.