While buying 2 of these has reduced my stress level over getting home in time for feeding my cat & dog and given me back a social life, unfortunately we are only able to use 3 of the compartments and have had to stick the unit together with gaffa tape.
Why? Because the cat is at it ALL day trying to get at the food. She can not only open the sliding cover, she has taken the unit apart (I came home to it lying in pieces on the kitchen floor) and eaten 4 days worth of food in one afternoon. So the gaffa tape has gone on in 3 places and one compartment has to remain empty at all times.
And my cat is not a huge tom-monster, she is a very small Aussie Mist (aka - the food stealing breed) - just very very persistent.
So while I recommend purchasing one of these, just beware of the relative ease the unit can be broken in to.
Also, C size batteries are expensive to buy and sometimes difficult to find. Especially if you want rechargeables.