It all depends in the winter I had a blast with my one I made waterproof. Got it dirty took it in and threw it in the shower and hosed it off with the shower head. I was also running plastic bushings where ever I could , and would hose the few I didn't replace with bushings down with WD-40 after every other run.
While running it was a good thing it was waterproof cause the snow covered some deep potholes up where there was water under it and my RC dived in and was completely submerged. If it wasn't waterproof all the electronics would have fried.
Now if your going to run it in a condition where you will never be near water than its pointless.