I demo'd both these skis at Bachelor over the weekend. Both in a 184cm length.
Me: 6'- 175lbs
Current Skis - Rossi S3 and Fischer Big Stix 110's. (Both 186cm)
Conditions were wind blown, with some wind, accompanied by -40F wind chill, which made for skiing on wind blown groomers. You get my drift. (No pun intended)
In any event, I skied the K2 Pinnacle 95's first in the morning. First thing I noticed when hitting the Outback runs on hard corduroy groomers, is that there is quite a bit of tip rocker in this ski. The tips do chatter at you when you get going. A bit disconcerting, since I'm not used to that sensation. The skis do carve nicely, and they handled the crud and wind blown junk off the summit chair, and after getting off-piste a bit found that the ski was stable and allowed me to go at speeds I might not otherwise go in such conditions. There was a section in the bowl with some wind blown crust, and the ski just slayed it. They feel a bit funky in the trees in cut up pow. Might of just been me though. I couldn't really tell if these would be good in untracked pow but I kept thinking the tip rocker was just a bit too much. Moguls were okay, but that darned tip flap would crop up now and again. It was a fun ski on the groomers, and easy to rail on. Quick edge to edge but at the end of the day, it is not a ski I would plunck down my hard earned cash to buy.
The next ski was the Volkl 90eight. Light ski, with very little tip rocker, and minor camber. It's a Volkl, so it carves very well for the 98 mm waist. It was very stable at speed. It carved like a champ, and was surprisingly easy and fun in the moguls. Off-piste it is a bit more work as the tips tend to slice through rather than float over the crud. I dove into some trees off of Ed's Garden with some cut up pow, and the sensation of floating is not there. I doubt this ski is the ski you would grab for anything over 6" of fresh. But on a day like I had them out in cut up and packed powder, and on groomers it was a very fun ski. It's not as versatile as the Pinnacle 95 but I had a lot of fun skiing on the groomers, and bashing down Coffee and the moguls in general, which I normally don't do much of. The length felt just right but there were a few times in some crud and off the summit chair in variable snow that a bit of tip rocker and maybe a few more centimeters in length would have been nice. They had just enough dampness and lively feel with stability that one would want in a ski. Because I already own a Rossi S3, that I really like, and still generally ski 80% of the time, not sure that I'd pull the trigger on the Volkl's either due to lack of float in powder, or at least perceived lack of float.