Bob - good question. I just put a pair of LiPoly cells in a Rare Bear, and it really screams now. I have yet to run the battery down - I always run out of time before I have to stop flying.

Frankly, I don't think the battery and charger were that much more than their NiMH equivalents.

I do still use NiMH in another plane that will already fly 40 minutes on a single battery. I think LiPoly's would be a waste in that one.

Dan.