I also use one. One I bought. The ones that come with the radio are not real comfortable. I flew 10+ years with out one. I find my hands are more relaxed with it. The only drawback(besides the prop thing) is it's hard to see the timer on my 9C with the strap. I have also heard good things about the tray. For a thumb only flyer like me I don't think it would work correctly.

David