They are very practical. I have three sentences. I noticed that the large piece slipped as I drilled a lot of dowel holes, but I didn't tighten it as much as I should. The good thing is that they don't damage the wood surface any better than a block of wood, especially in hard-to-reach places. But hold her tight. If you're doing fabrication work and drilling lots and lots of holes, you may need a metal stop, but even then it should work fine. My only concern, hence four stars instead of fiveβ¦