Magic I was a big supporter of redundant batteries,(ask silversurfer ) however 3 of us fly 28% planes at our club and I am the only one doing so with 2 receiver batteries. I fly with duralites which have to have regulators,my second battery is connected with a "Y" Battery- Rudder servo- rudder port on receiver, with a switch and regulator in between of course,this has proven to work very well, I was somewhat skeptical until Tom posted the same set-up on here. The reason for this is that I was short of spare ports on the receiver, if you have open ports you can plug your second battery into any one of them and do without the "Y"