Jetro,
I just purchased one of these off of a gentleman at a local archery shop for my Pro 38 and the one thing I can tell you is that they are extremly versitile just for the fact that you you can add and subtract wieght to customize your outfit. That is one of the reasons I bought this set up. By the way they are not cheap, but you get what you pay for and from what I heard they perform really well.
Bow Tech shooter thanks for the info.