I also went last Friday night to see Tenet and had a good time. It was my first drive in movie, so I wasn't sure what to expect, but I thought, overall, it was a pleasant experience. There was one audio glitch in the middle of our showing, but they fixed it quickly and we didn't really have any problems. We brought a small AM/ FM radio, rolled down the windows, and snuck in our own snacks (I don't think you're supposed to do this, but no one really checked).
Pro Tip: we arrived at 7:30 (movie started at 8:30, gates opened at 7) and it was already about half full, so get there early. Also, we were expecting it to be a mess to pull out of after the film, but they directed traffic pretty efficiently.
Also, we talked to our friends who had gone to the drive in at Sawyer Yards ($40 a car/ Moonstruck was $25) and said that screen was small and poorly hung so that if you weren't dead center, you couldn't really watch the film. At Moonstruck, we were off to the side a little bit in a small sedan and had no issues.
My only suggestion is they dim the string lights near the concessions during the movie -- a little too bright for movie viewing!
(Edit: Spacing)