That's great. Is this with a recent car or firmware? When the Tesla owner advisor came to my house last summer to try Auto park with an X, it worked great the first time. He tried it again to confirm that it would work, and the X turned instead of staying straight. I appreciated his honesty and declined to get the X since I couldn't count on comfortably parking it in the garage. He asked me if I would consider the S.
I got the September 2017 build. For a few months, Summon occasionally would turn the wheels when trying to get out of the garage. After one of the updates a few months ago, it hasn't done that although it would still sometimes abort early when there didn't seem to be a reason for it to stop.