I currently have 5 giant scale gasoline powered planes which I fly. Not a PCM receiver in the bunch and no ignition noise or glitching. All have electronic ignitions, CH Electronics and Falkon. Most have shielded ignition caps and one doesn't (Brison 6.4 twin). I run Futaba, Hitec, and FMA receivers, all with Futaba transmitters (2).

PCM will work fine but don't let anyone tell you that you must have PCM for gasoline engines. Good installation is the most important thing to prevent radio noise.

Ken