Ooooo. I like those aluminum skis. I have DuBro plastic and they hold up fairly well. I keep spare gear set with skis for two of my planes so I only have to remove four bolts and can swap from wheels to skis without reattaching and tensioning the springs & torque rods.
http://www2.towerhobbies.com/cgi-bin...?&I=LXWH30&P=7
One of the guys in our club laminates his own out of thin ply veneers and they look great on his vintage biplanes.
Don't up the nitro. That would make the engine run cooler. The nitro lowers the combustion temp so an engine can run leaner and therefore faster.
Cold air is heavier, you'll have plenty of power as the prop has more to "bite".
Plastic coverings get brittle, but should not be a problem. Don't drop anything on a wing (I learned that the hard way). The covering splits with a "BANG".
Skis don't stop as well as wheels on grass. Allow for at least 2X the landing run on snow.
Definitely look into the "glommits" or other fingerless gloves. I've got about four pairs kicking around. Get a hat with ear flaps or some ear muffs - regardless to how they look it is a great comfort when you're hands are busy flying. A poly scarf, too. Looking up the wind goes down your neck. Sunglasses definitely. Polarized even better.
Keep an eye on the batteries. They seem to have less staying power in the cold.
Bring coffee and hot chili.