ok, but flawed
We like the large size of this flap, and our cats all like it much better than the standard (i.e. small) sized flap that we previously had.
Unfortunately though, we have had the same issue as the previous reviewer with the tabs that lock the flap. One of the red tabs (which stops the cats going out) became began to shift out of position easily and jam the flap, and the cats would end up getting locked in or out. This was made worse by the tendency of one of our cats to charge through the flap at top speed - every time he'd do this, this tab (and sometimes the others too) would shift and the flap end up getting stuck. So we've now removed the malfunctioning red tab completely, which isn't ideal either, since one side of the flap isn't completely secure when closed, and our largest cat can force his way through when he puts his mind to it!
Another issue that came up even before the tab became damaged was that all of the tabs get clogged with mud very easily, making them difficult to move. This is a problem when the weather is wet, as the cats bring in lots of mud on their feet, which seems to quickly find its way to the edges of the flap. They're also difficult to clean.
So I want to like this flap more, as it's a nice size and shape, and is generally good, but it's let down by the poorly designed locking mechanism.