Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: Good idea but needs to be more durable
Review: I have gone through 2 of these in about a years time. I like the fact that the bits are so easy to change, which is what attracted em to them in the first place. After 6 months or so the ball retainer for the pilot fell out or was broken, which meant that you had to start the hole and then take the pilot out or it would fall out on it's own. The second one was destroyed when I was drilling with the 3 inch hole saw that came with the set that I purchased, and the bit actually bound in the hole and the stub that is put into the drill chuck actually bent. I am a professional remodeler and do use my tools, but I never abuse them. I can't afford to keep replacing broken tools. If you are doing light duty or small diameter holes then this is the system to get, but don't expect the mandrel to last through much in the way of heavy use.
