I own two of the Ayr model with the adjustable Sherwood tree. They are very well made and an excellent value. If you use Google, you'll find a link to a horse grooming forum where I posted pics and a writeup. And you'll also find a discussion on a Maryland discussion board.
I use the one with the blue gullet in it. The other one is too narrow and I haven't gotten around to getting it changed. I don't jump, so I can't comment on the "position" or anything. The economic depression derailed my plan to buy a horse, so I ride a few borrowed ones.