Well i live in big snow country and probably have a longer winter season than anyone else around here (usuall first snows start mid october and last through the following april). I've been running nitro and electirc trucks in the snow for the past 7 years and never had a problem. The only precautions i've ever taken is to either start my nitro inside or heat it up to running temperture before starting it. If you don't do this the engine will wear and re-fit itself for cold running. It'll run great in the cold but run like crap once its summer again.

As for water damage and crap like that, i just don't even worry about it. I run my stuff when its COLD, so melting snow isn't a problem. Just make sure you've got sub-zero temps [:-] and use some compressed air to blow away the snow before going back inside. LoL just typing all this stuff about winter is making me shiver....