Review on Fixture Adjustable Diamond Centering Openings by Meech Elliott

I bought this to line up some holes in a marble tile. A suction cup needs a perfect surface to stay safe. Even then, the tool rotates slightly, causing the hole to move. The screws holding the bearings came loose on the side of the hole saw - I ended up running the drill bit backwards to prevent this. Since the tile was loose, it would be better to attach a piece of wood with a properly sized hole to the tile as a guide. To top it off, the bearings got rusty from the cooling water I used.