thanks, we have posted in the car forum, and nobody has a straight answer. im using a brushed motor so the discharge rate from what i understand is well within the limits of the lipos, it is a thunderpack 7.4v 4200mah pack that i was looking to get. i race in stock class and these batteries are about 1/2 the weight of the nimh so it would be huge in stock racing. when you say dont bang the battery can you be more specific, if i go over a jump, are they that unstable that i have to worry, what happens if a plane has a bad landing, will that destroy the battery?