McGrath: "I find it easier to use the Kyser because you can move it round one handed, even in the middle of a set of tunes."

Has anyone tried the Glider Rolling capo (www.glidercapo.com)? I'd like to know how well it functions for mid-set key changes. It looks pretty effective on the video. I've used a Quick Draw with mixed results and the Kyser is better than most for that purpose but still a bit clumsy, for me, anyway.