I had my Hale pet door installed 24 years ago. My German shepherd had learned that if she rattled the blinds at 3 a.m., I would get up and let her out. This became a game. (If you don't want a smart, manipulative dog, don't get a German shepherd.)
The Hale pet door solved that problem. It was installed in a sliding glass door.
I just had a new flap put in. This is the third flap. The current German shepherd goes in and out like it's not there. The new flap was installed by Hale. David, the installer, did a beautiful job.
If you need a pet door, I recommend Hale.