I have a 2014 S. The MCU was replaced under warranty four months ago, the upgrade was not an option. I really tried. I did get the LTE upgrade. In my car, the browser might as well not be there, even with wifi. Service center says that's the way it is. I very rarely have more than one bar on the LTE screen, even when phones in the car have maximum.
When they were replacing the MCU I had a loaner car that had MCU 2. It was somewhat akin to leaving a dial up connection and being on cable, it was fantastic. I literally cannot get a web page to open within 20 minutes in my car, (post MCU change, or pre), in the loaner it was seconds, anywhere.
Has anyone done this to an older car and seen a change like that? It would be worth it to me if it performed like it did in the newer car.