If I remember rightly....
... I phoned them and spoke with a very nice young lady who was really helpful. I paid by credit card.
Yes, they do work really well. They only effect the position by an inch or so, up and towards you, but it makes all the difference. I'm 5'8" to give you an idea of comparison for yourself. They upped the distance to aches from 50 miles or so to 200+ miles. Then I got my Corbin seat, and I now never get any such aches.
Heli's are pretty expensive, but I think they're worth it if you can afford it. They're also very well made and look pretty good.