What he said. I haven't used one but form looking at it it looks like a cross between a set and a chipper. I think if you have bot a set and a chipper that would be better, but if you had neither it may be able to sort of do the job of both
x2. I use the handset all day, the point and tracer just when needed, but the set gets used on every stoneI would say my carbide set is used the most of all my stone tools.
Mostly all we get around here is the limestone and sandstone. Some of the sandstone is fairly hard but it has striations in it unlike granite, it likes to chip off when trying to cut it against the grain. Watching the videos, and the stone they are using, they just don't look like they would be that great of an improvement for my environment/material.