RE: Lipo batteries in your transmitter
For couple of months I have been successfully using 1800mAh 3S LiFe pack in mine JR 9303. It fits perfectly in the battery compartment and has a JR plug. The difference to LiPo is that when fully charged LiFe are at 11V but after couple of minutes falls down to 10V and stays like that for a very long time. Last month it dropped to 9,9V so I decided to charge it just to see how many amps would go in, and it was 810mAh. Since then it is still at 10,0V.
For me the main advantage over NiMh is that I can charge it absolutely safely at 2C and that there is no memory effect for partial charging. So if I have any doubt about the bat condition I just put it for 15 min on the charger and its more than enough.
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14076
Velco