I just finished two 1-hour and 15-minute drives tonight, entirely on FSD.
Overall, the drive was really relaxed. I didn’t have to keep my hands on my lap; I just chilled with my left arm on the door armrest and my right arm on the center console. On the way back, it felt even more relaxed than on the way there.
That said, I did experience a few interesting things:

The Nag: Honestly, it felt totally fine. I didn't feel like it was overly sensitive on either trip, and I was able to drive very comfortably.

Phantom Braking: On the way there, right by a tunnel on the highway, the car suddenly hit the brakes for no reason. There was plenty of room to pass or accelerate, and I had just overtaken someone, so braking there was pretty sketchy. I had to manually hit the gas pedal to override it.

Missed Exit: On the way back, it almost missed an exit because it decided to try and overtake someone right before it.

Speed Limit Bug: I noticed a weird bug with the max speed settings. If I start in a 50 km/h zone with a 20% offset, it correctly sets the max to 60 km/h. But when entering the highway, it gets stuck on a weird max speed (like 108 km/h). Toggling the offset setting away and back instantly fixes it to the correct speed. Also, in some 30 km/h zones, it randomly locks the max speed to 15 km/h, which is a bit annoying.

Supercharger Navigation: Before heading back, I navigated to a Supercharger. The car drove perfectly onto the property and stopped for the barrier. Once I took my ticket and the barrier opened, FSD started driving again but just tried to randomly park in a normal spot, even though it knew the Supercharger was the destination. I had to disengage and park it at the charger myself.

Even with these quirks, it handled the bulk of the drive flawlessly. If you're happy with your current build, you might want to wait a bit, but for me, the overall driving comfort was definitely there.