As a homeowner and avid DIY enthusiast I have found them to be well constructed, durable and easy to use. I only have one suggestion. Pilot holes have a guide to start the hole before using a larger countersink bit. This guide has a small ball bearing for centering, but not really. You have to be a little more careful to make sure it's centered. I marked the clip and guide to make sure they are centered every time before using the starter bit. Also, the countersink didn't go all the way into the hole, forcing me to move the clamp to finish the hole. I had to leave a clamp in place while I did this to align the cabinets and move the clamp and check alignment to finish the countersink. It's not bad, but it does require care and planning. However, I like parentheses.