Purchased to cut a few holes in hard, large tile. Hole saws look flimsy, but they do the job well. We used a low-speed cordless drill and a spray can (a bottle of recycled glass cleaner) to keep the tiles wet. Scrap the tile and then use that tile as a positioning device to keep the saw stationary when it's started. Once we got a few millimeters into the tile we were able to remove the jig (and the water only runs down the side of the hole saw so the jig doesn't really cause any problems.)β¦