I use the SwitchGlo Pro, very small and uses the receiver battery. I set it up to come on at 1/4 throttle and below. Works great. You don't have to use a 4 cycle plug. Enya 3 or 4 work fine. I actually used an Enya #5 this summer when it was over 100F to stop pre-ignition on 30%.

You can knock the beep down by simple tapping the hole and putting a very short M3 screw in it. I don't like 80 dB while I am starting. You may.

I use the Sullivan Head Lock Remote Extended for the plug.