Typical Futaba QM40 setup:
1) RX - R617FS
2) Elevator Servo - S9650
3) Rudder and Engine Kill - S3102
4) Aileron Servo - S3002 (or replacement) or S9650
http://www.rcuniverse.com/forum/fb.asp?m=11349006
I've been using the 700 mAH Life pack with good results. No regulator is needed.