Just got my car back after having HW3 upgraded from HW 2.5. I stuck with my MCU1 since I wanted to see the difference before spending $2,500 on the MCU2 upgrade. I'm stuck on 2020.12 for now, instead of 2020.15 or 2020.16. The alert that I was about to go through a red light happens much earlier now (a good distance beforehand vs. almost going through the red light), and AP seems smoother, but that's all I've noticed so far. will report more once I've gotten the latest software update.