Being a total gadget whore, I ordered the thing.
Tried it for 1 day and, after my neighbor wouldn't take it, threw it in the trash.
The rubber bolt cover abrades immediately: no big deal, since it's really not needed.
Once tightened according to directions, and then the chain is set, the bolt is really very hard to get loose. No big deal: just remove the handy plastic knob, exposing the hex head on the bolt and use a socket wrench and ratchet handle.
But the deal killer for me: The chain was way too tight, when using according to directions, and when I compensated to where it was about right, I found that I was pretty much just doing my usual SWAG approach, which I'm good at and which has worked for many years without no fancy gadget.
Summary: A solution in search of a problem; that creates more problems than when I started.
But then you may like it just dandy.