Why would you need to remove your hand from the joystick, would be my question. I've shot with them for years. I don't...and I don't know anyone else, that lets go of the stick while pulling the trigger. I set the rest tension to where it moves easily, but still stays put when I let go.....to load the gun. I don't know why else you'd need to let go and wouldn't recommend it.
Aside from that question, I think it's something that, once you use one, it quickly becomes second nature. For me, it's the only way to go on a score target, be it rimfire or centerfire. RTB means nothing shooting for score, IMHO. To me, a joystick rest is much faster at navigating a score target. This is worth a lot when you need to be running or getting from sighter to record quickly.