I bought a pair of K2 Hellbents in the 189 last Feb and have been surprised at how versatile they are. Something huge and stiff might be somewhat better in cut up and crud, but the combination of rocker for float and general heavy hugeness for stability works pretty well once the fresh is worked. Despite their weird looks, the Hellbents have a pretty traditional sidecut (28M IIRC) and are surprisingly fun on groomers too as long as the snow isn't too hard. The tips and tail flop around but it doesn't transmit through the ski and they feel like a big ole GS ski.
I've heard reverse side cut/reverse camber are even better in crud, but have no 1st hand knowledge.
As you might expect, the Hellbents pretty much suck on boilerplate, hardpack and bumps. I went back to my Volkl Mantras once the spring ice/corn/slush cycle was on, as well as when it hadn't snowed for a long time.