I like that they are heavy. However, the movement of the outer part of the pen depends on the operation of a tiny set screw. I haven't used it much and it sat idle for a few years. Now the pen part doesn't slide up and down as easily. Since it's not cheap, I'm curious how long it will last. I hope that at least holds up through the wiring of a house. The pilot drill is also about 2 inches from the holder. Not long enough for multiple tall hole saws. A generous 3.5 inches would be desirable.