I am flying a Diddle Bug with a 2 cell 250 Lipo HR winters here in upstate New York tend to be cold. Cold as in its already been +6F here. The Mon. after X-mas it started at 39 and fluctuated between that and 28 and up and down. The Battery was indeed weakest at the lowest temps. I did have a few very nice flights with my EASY 4oo with a 6V 400 ans 8 cell 1300 nimhi. My friend Ed, said Nicads perform well in the cold, then nimhi and then Lipos. Have fun this Winter. Lee