My cats were driving me near the brink of insanity with their whining for food at 5am.  As a last ditch effort, i decided to buy this automatic feeder, even though i assumed my cat would figure out a way to sabotage it.  This machine is a godsend.  My cats can't get into it, and they don't whine for their food nearly as much.  Instead, they sit patiently in front of the feeder from 5am until it goes off at 6:15.  it's just so wonderful!  If i could change it in any way, it would be to add a clock to it to set precisely when the machine goes off.  It's a little inconvenient how you have to be at the feeder when you want to change the time.  Meaning if you want to change the time from 7am to 5am, you have to be at the machine either at 5am or 5pm, since it works on a 12 or 24 hour interval.  If your cats are whiners, save yourself some suffering and buy this now!