It is my understanding that the clamps are preset at ~22 degrees, however you can adjust the angle that this produces on the knife by varying where you fix the clamp. Joe Talmadge has used the clamps he would be able to provide more information.
In regards to the stones, I have no idea how they work. However when I looked at them before they seemed expensive. As well when I contacted them for grit information they didn't have any idea. Personally I would go with japanese waterstones, or DMT benchstones, the latter will cut any steel with ease.