My CP is stock, whats a good lipo battery to use? without breaking the bank.

I used a 1250 MAH Lipo on mine, and got 20 to 30 minutes of flight time total per charge, but I had a problem back then with burning out tail motors. I here that going to the dual motor setup fixes the problem. I tried the resistor/diode harness, but that didn't seem to help at all... All those tail motors drove me to the purchase of a used nitro heli. Im very happy now, but I don't fly in the house anymore. lol