Just picked up my car with the updated hardware. Dropped the car off at 8 am and picked it up at 2 pm same day. The car is almost 2 years old and has never been to service, so they also did a couple of service bulletins during that time. The car is a March 18 build. My August 18 build is not yet qualified for the update, so if your car isn't Q1 of 18 I wouldn't bother them yet.
Update went very smoothly. All data was preserved except phone bluetooth. Key still worked, homelink, radio stations, presets, all worked I just had to relink the bluetooth to stream music and get calls.
The visualizations were really nice. I never realized how many lights most intersections have. 5+ would showing up accurately on the limited test and I think it worked smoother in AP, but it worked well before so maybe it was just all the trash cans, cones, turn arrows, bike lanes giving me more confidence. Some cars still disappear at intersections.
Overall, very easy, but nothing really changed to make it a must have yet. Will check in a few months on the other car if I don't hear from them.