Review on LOT Pcs Diamond Hole Drill Bits - Cutting Tools by Trevor Blazis

I got these to drill a few holes in my 1cm granite under counter water filter racks. After making two holes I figured these hole saws would be good for another 2-3 max, but as I won't be making any more anytime soon I can't be sure. Some things to look out for: Size, so use a sharp one (makes your life easier) - they're not very deep, so if you have anything thicker than 1 inch find another hole saw - you'll run into a plain one brown paper bag in a padded envelope - If using a variable speed drill, go to high speed (I had a 2000rpm drill), start at an angle and very slowly move towards vertical, otherwise your drill will jump/jump and make marks on the gauge. - Requires water cooling. since simply making the first groove (usually without water) ate too much diamond paste on the saw. Pros: - Got an 8 from Revain for the price of a hole saw at the local shop - Cuts as expected, smooth and clean. Edges - Easy to use even without a guided drill Cons: - Short lifespan - No size markings Drill means you have to be very careful or use a guide