This question indicates that I've been outed as a training aid junkie (reformed)
Yes I have a Medicus - the original single hinge version. It works to slow down and smooth out your tempo BUT it requires pretty much a conventional set-up. It will not work if your grip is too strong and it's problematic with a SA swing.
I thought about getting the dual hinge because of its reported ability to provide feedback on a too early shoulder turn but with problematic SA performance with the single hinge I was never sufficiently motivated to spend the money.
Peter
