Some people like the "click" in the thottle. Some don't. If you don't prefer it, most radios can be opened up and adjusted to not click or to be a little lighter on the clicks. I do a lot of electric 3D stuff and I hate the clicking. I opened up my Flash 5 and bent the little thing that makes it click to where it barely touches the gear so I get a slight bump but no click.

I'm not sure why heli's don't have it....maybe the same reason?