Excellent quality, this item cuts very smoothly through my stone countertop and sink. I was apprehensive about this DIY project because I didn't want to destroy an expensive kitchen. I also didn't want to pay someone $100 to come and drill a hole. I almost took off a star because the water actually spilled out of the plastic cup/guide but compared to the mess the dust makes this thing awesome. If you need to install a faucet with a filter, reset switch, etc., just buy this item and get started! I have a Makita 18V drill bit. In drill mode (not hammer drill mode) start at low speed "1". Use a small angle and then straighten it. I had to put some pressure on the drill, but I took my time and let the drill do its thing.