It works fine, but...
It works fine, but the little quartz motor on mine conked out while I was on vacation. I tried to take it apart but the motor unit is heat-fused welded to the case, so it is not replaceable. The 800 number to the manufacturer put me in touch with a very knowledgeable lady who verified that the motor could not be replaced or serviced, so I had to buy a new one. The manufacturer does not sell direct to the public, so the lady advised to check the net because prices vary widely. PetGuys delivered promptly, and sent me a personal email when I messed up my credit card info, and another personal email to confirm I corrected it properly. No complaints with the operation...it's very adjustable. But you ought to be able to buy a replacement motor.
ProsAdjustable doses easy to operate and calibrate
ConsDied after 3 years and motor not replaceable.