This plunge base is great for hand-held use.  It plunges smoothly and locks positively without any change in depth when you release the locking lever.  Its worst fault is the lock that retains the motor to the base.  It's a kind of wedge that is tightened with an Allen key. Its position means you can only turn the screw a half turn at a time with a standard Allen key.  A long T-handle Allen key solves that problem, but not its other fault, difficulty removing the motor from the base.  That same Allen key must be loosened several turns and then the block that acts as a wedge has to be loosened by tapping on it.  It isn't that difficult but it just seems a less annoying method could have been designed to hold the motor in place.