Yes, I know the systems. But everything which I had in hand, seemed for me too weak, too fluky, too insecure.
The hook itself (because of the system) always has a little movement in its attachment. Gives me a very uncomfortable feeling when hanging out.
In brief, I don't trust them.
Looking at the kitesurf scene where they have a lot of experience with emergency releases, they only use release-systems in the ropes themselves. And even that is not always 100% working when needed.
Maybe someone has better experience, please convince me.