Elite 1500's from Hangtime hobbies. Should get you 4-6 10 minute flights depending on how you fly and what size airplane we are talking about. These are good little batteries, low impedance so very little voltage drop under load. If you think you need a little more power, go with the Elite 2000

Myself and most people I know use 2 batteries into 2 switches into 1 receiver. 2 receivers is not required

http://www.hangtimes.com/giantrxpacks.html