...the cats also use the flap. But they already used the previous dog flap and are quite independent and love their freedom (and will overcome any obstacle). It might be more of an issue for timid cats.
We changed our non-insulated PetSafe flap for this one and it really works. It is far more draft-free and insulated!
We removed 1 star because the yellow insulation layer isn't great to look at. It doesn't really bother us because the flap is installed in our basement.
Also the installation is that easy - you'd need someone who is handy. A YouTube video would be helpful!