My limited experience with them has been favorable. Scary sharp, scary fast. My friend who owns the one I got to play with told me that you can round the tip if you finish the stroke wrong.
Custom knife makers use belt sanders and jigs to grind and finish an edge. This seems like a scale model of the same thing to me...
I am going to have to buy one.
The Sportsman's Warehouse in C.Springs has one sitting out on the counter that you can test drive. Maybe one up your way does too?