Purchased 6 years ago, amateur use + 2 moves along with partial renovation each time. Used with drill and screwdrivers electricity and battery 12, 18 V. Almost no signs of use on the bits! Excellent contact / locking with each screw. The head never broke from poor application only from wrong angle or very hard material screwing. The bits are magnetically attached to the holder/adapter and even today almost no play! It is clearly of a professional tool level! Only problem is that the plastic holder fell many times and broke one of the positions that holds 1 torx bit, nevertheless it still locks in the folded (flat) position.