I used my short ass invaders in pow for a season before I got my bacons, and they kinda did the trick. You won't be able to ride pow the same way you ride packed snow though (and despite the fact that the one guy thinks this is stupid, you will almost for sure need to keep your weight a little backseat unless you want to experience the joys of tip dive). That said, pow is pow and if you've never skied it before it's gonna be fun as hell regardless of what skis you're on.
Now that I have my bacons though, skiing pow is even more fun and allows for a good centered stance. A rockered ski would only be even more drastic an improvement. So demo/rent a pair of fatties if you can, but like everyone else said, probably not worth actually buying fat skis for one trip. Your bangs will do.
Skiing's rad, hating's bad.