I just got back from a 3600-mile drive in my 2023 MYP. Phoenix to Iowa and back, via Utah, Colorado and New Mexico. I doubt I drove even 100 miles myself, and my girl was similar in her shifts. FSD 12.5.1.3. One safety-related disengagement in Colorado, and lots of 'supervision', especially regarding speed limit changes. Except that one disengagement, all interventions and disengagements were ultimately because I wanted to go faster than FSD wanted to do.
Mostly everything was quite relaxing, once you get used to what it's likely to do in some situations. It was uncanny a lot of the time. Certainly a better (safer) driver than either of us, with the caveat that we were also supervising it closely. In towns or slow traffic it was pretty good. I did have a lot of patience with it, getting used to some non-humanlike driving at times. But never unsafe.
I found one road that was so annoying I finally lost patience and took over for about 15 miles. 491-s southbound through New Mexico. Besides the ever-present drift-down in speed and failure to pick up new speed limits, and constant annoying speed changes at speed limit changes (though nobody else slowed down), FSD kept getting back in the right lane after passing a car. The right lane was extremely bumpy, and FSD kept overriding my cancellation of the turn signal to prevent it and insisting on getting in that lane. No cars coming up behind me.
Once on the interstate, FSD reverted to full highway stack and worked pretty well.
But 2-lane country highways with 65mph speed limits? I finally just realized I was trading one kind of cruise control for another. With my ICE cars, it controlled the speed and I did the steering. With my Tesla, FSD does the steering and I keep my foot on the accelerator. Annoying, but works ok to stop the drift down in speed. ("Cruise control will not brake!" message.)
We saw about 350 other Teslas on the trip, including 5 Cybertrucks. And another 100 or so in a delivery lot near Denver.
All in all, an awesome drive with amazing scenery. And Kayenta just opened up, so going through northern Arizona just got way, way easier.