My recommendation ... go out and see if what you have is OK. If were you though, I would spend a few dollars, and get APC 11x5, APC11x4, and maybe an APC 10x5. Then try each one and see what works... I always recommend APC because of personal preference, and experience, but there is no better alternative than trying things yourself.

The smaller pitches will give you slightly more RPM, and way more thrust that will be better at overcomming any resistance on the skiis. It also gives you a better braking mechanism when landing, but it will reduce your top-speed. If ou are a speed daemon, then you will feel cheated with a smaller pitch.

On the flip side, I don't have snow experience (yet), but what I have recommended to you is exactly what I am going to do when santa brings some skiis for my plane!

In my ski-on-a-plane research, I have heard it said that when the snow is really powdery, then the best thing is to fly off floats!

gus