Re: Riding with GPS?
Sometimes they don't work very well in heavy cloud cover, dense trees, or in the bottom of steep canyons--be aware.
They may take a few minutes to get a satelite fix when you first turn them on. Have it running while you are unloading your sled at the sno-park and mark your position there before you take-off, this will give you a good "starting waypoint".
Keep the unit warm (inside pocket) when not using it. Some batteries don't work very good in cold temperatrures. Don't trust rechargable batteries; when they begin to get weak, they will die very quickly with little warning on the unit's "Battery Indicator".
Get a unit that can be used with an auxiliary antenna. I mounted my antenna using a Velcro strip on top of my helmet. This allows the reciever to get a fix on the satelites behind you when you are riding and greately helps the accuracy of your position. They can get signals through the winshield but not through your body. It also allows the unit to keep recieving if you have the receiver in your pocket.
I recommend Garmin. I had a Magellan 2000, and it only lasted about 6 months. I have had my Garmin GPS II Plus for about 3 years now and it still works flawlessly. It also recieved more accurately and had better mapping features. Other (newer) Magellans might be fine, not sure; just my experience with the two main brands.