Originally Posted by bjohansson
Technique is necessary. Take a lesson. Learn what is right.... Seriously, work on your technique and if you find that you want to keep venturing out into the soft and deep, then consider buying specialized skis.
The problem with this statement is that so much of powder "technique" - including what one would most likely be taught in a lesson - is an artifact of using skis designed for groomers to ski powder. Notably all that weighting/unweighting porpoising stuff (whose main purpose is to decamber your ski so it can rise/turn).
You wanna get out and ski powder painlessly? Get thee to a Pontoonery! And grab something rockered and fat. Seriously, a 78mm ski ain't gonna do jack to help you learn to ski powder. Nor will an 85. Can you learn to ski powder on them? Heck yes! Do some people prefer to ski power on them? Yup. Is that the easy road to powder fun? Uh, no....
The notion of incrementally working your way into powder is just silly and needlessly painful. Don't mess around with baby steps in gear and technique that will most likely get you nowhere anytime soon. If you are going to get skis for powder, and want to have fun in powder, get something in the mold of Pontoons, Hell Bents, Lotus 138s, Praxis, EP Pros, etc... You'll be hooting it up in no time.
A couple additional thoughts: 1) in general this class of ski is good in soft snow of any sort, not just powder - things like slush and soft cutup and 2) I assume when you (the OP) say powder you mean powder and that you want a ski truly oriented towards powder (& other truly soft forms of snow) - and that it makes sense in your universe to get such a beast.
And if you can't see yourself on a rockered ski, at least get something conventional that is powder friendly or powder oriented - Bacons, Sumos, Gotamas, Rubys, whatever... The previously mentioned Watea 94 is well regarded, but is on the narrow end of what I'd even consider (as would be a Seth)...