You need no seperate the ignition system from the rest of the radio system by as much room as you can. One RX will give much better range than 2 will. JR official stance on it is one RX is definetly better than two and they are dead right as I have done range testing to prove it myself.

30 paces is a joke. I have one JR S-PCM Dual conversion RX in Tom's Edge and I get over 100 paces engine off and over 100 paces engine on. I actually don't know how far it will go I stop at 100 You have some major problems. Like it has been said PCM is no cure, but will only mask a problem. If PCM RX's cut out like you said then eliminate things one at a time. Toss one RX for ground testing sake and take out any and all battery backers and etc. you have. Use only one RX pack and one ignition pack. SIMPLIFY. Go from there. Your switches are all by each other you said. Could be it as my ignition switch is at the very front and my RX switch is at the very back of the hatch. As far away from each other as possible. RX pack is at the back of the hatch and ignition battery is under the cowl on the inside of the engien box. Distance is the key.

Let us know how it comes. Above all else DO NOT fly that thing until it IS right. You have invested too much and the reward is just around the corner of a great plane. You will get this sorted out and then the rest is pie.

Norman Ross