"I have always had a problem drilling porcelain tiles, this just does the job brilliantly have never been able to drill more than a couple of holes with a drill bit no matter how slow I drill and spray with water or how much I pay. In my view worth double. The bit comes with a piece of plastic which you fill with water, and it feeds automatically onto the drill bit. Only criticism is the water feeds quickly, have a bottle handy to re-fill. I used on lowest speed and so far drilled 4 holes and still looks as if it can handle at least a couple more."
"I bought one of these to fix the shower rail mirror & loo in my new bathroom on hardish ceramic tiles. the drill just about did the job but lost it's diamonds before I'd quite finished. The water resevior has suckers but don't rely on these to hold it in place It's really a 3 hand job 2 to hold the resevoir and guide the bit and one on the drill. It may be I didn't keep the water constantly on the drill as it runs out pretty quickly. Anyway no cracked tiles which would have cost more --finished off the last 2-3 holes with 4mm masonry bit to start with and then finished off with a bigger one. I expect the bigger drills are even more difficult to keep in place so get someone to give you a hand."
"Bought this to drill several holes in grade 5 porcelain tiles- I was disappointed, took literally 30 mins to drill one hole with continuous water cooling, after 4 holes I gave up and bought the Erbauer diamond drill bit which drilled the remaining 7 holes in less than 30 mins total and without cooling!"