I revieved an e-mail answering some questions.
They state the rest will stay up for a few inches before droping. I have the impression this is not adjustable.
The rest WILL NOT drop if the bow is bumped.
It must be hooked to the cable, not the cable slide
and can be set up so the launcher stops short of the shelf.
I guess the only negative is that it has to be reloaded each shot, but thats no different than the trap door.
May just pull the trigger on this today
I have to get my junk box worth more than my rig