Drill America 1/2" Carbide Tipped Glass & Tile Drill Bit - DWDGD Series for Precision Drilling in Ceramic, Porcelain & Mirrors - Perfect for Bathroom Renovations & DIY Home Projects

I may or may not have used this exact brand, but I have used many (over 30) of this type before. They are very slow to cut, tend to want to walk on hard smooth surfaces, and the blades break off quite often. Make sure you use water to cool the tip constantly or it will break much quicker. would recommend the four tip ones as they last longer and cut faster and are less likely to crack what you are drilling. Also, this isn't the best price out there, which is why I chose this one to review. .