It has some realy obvious problems!
The entrance is pretty big and the second cat can easily fit in there and eat at the same time, as you see in pic A! The lid will try to close but with two heads pushing it, it can't.
From the back there is so much space that any cat can easily have access, as you see in pic B and this is a so obvious design flow that it is frustrating!
I solved those problems with some white carton and hard plastic sheet as you see in pic C. It works but it ain't pretty no more!