RE: change to lipo
it will work but I don't recommend it so use at your own risk. Yes a 7.4v lipo will work but the RX doesn't support lipo protection and it will run the battery dry. We all know that a lipo can not be run dry and it must not fall below 6.0V for 2 cell lipo. You can use it as long as you time yourself and don't like it run for more than 6 to 8 minutes and you should be fine.