Dry Heat:
Yes, the guides wear down. Perhaps in a few years, or longer, you'll need to replace them.
There is a way to adjust the angle you're sharpening at. Assume you've put the clamp on the stone. If you move the clamp further out from the spine, and away from the tip, the angle will go DOWN. If you move the clamp in on the spine and more towards the tip, the angle will go up. There is no real way to know exactly what angle you're sharpening at, of course. But you can do small adjustments this way.
So, if you like to get rid of the burr by double-grinding, here is what you do (Razor Edge recommends this themselves right in the instructions). When you're done sharpening, move the clamp slightly in towards the spine and the tip, which raises the angle slightly. Now take one swipe per side, using no pressure other than the weight of the knife itself. This almost always gets rid of what's left of the burr.
Oh yeah, as Cliff mentioned, do buy the smooth steel if you don't have one.
So, what I recommend you guys buy is:
- Small clamp
- Large clamp
- Smooth steel (if you don't have one)
- Book
- Video (a must!)
Whether or not you buy their stones or anything else is up to you. Me, I like DMT diamond stones.
Joe