I looked at these switches at one time also but after some research and thought it seems connecting the radio to the engine in this way goes against everthing I've read about ignition engines and proximity to radio gear. I'm really interested to hear what others have to say about these.
I would think a good switch would be the Zenoah kill switch sold by Horizon which is really nothing more than a toggle switch which when thrown, grounds the ignition current on mag ignition engines. Radio Shack sells toggle switches for much less than the $7 Horizon wants
http://www.horizonhobby.com/Shop/ByC...rodID=ZEN20000