I have used jr pcm recievers for years with no problems I also run the airal inside the fuse the only time I had a range issue was caused by the carbon fibre in the wings changing the freq fixed that problem JR does rate their recievers and servos to 6v but a fully charged 5 cell pack is close to 7v which is to high if you want to use 5 cell packs you need to use a voltage regulator I use 2 cell li-poly packs regulated to 5.5v