Check out Hangtimes Hobbies, [link]http://www.hangtimes.com/[/link], they are fantastic. My recent order for a replacement Rx pack for my R50 V2 came the day after i ordered it and I paid for no special shipping. You can also call them and you will get good advice, along with the clear and concise info on the webste. I put a 1650mah NiMH battery in my JR8103 Tx and I have gotten 13 flights between recharges and still had battery available, where as the stock pack was only good for 3-4 flights.

My stock 1100mah NiCD Rx battery was only for 1-2 flights so I got a 1950mah NiMH for my R50.