Personally, for me it doesn't even matter whose UI is better. We have two vehicles in the family, mine is a truck, wife's is a roomy crossover. Depending on the task at hand, I will drive whichever one is more suitable for my plans that day. Or whichever is standing closer to the end of the driveway if I leave the house first. I also travel 2-3 times a month and get rentals. I want the same experience, the same voice commands, the same saved info (map pins, addresses, podcasts) in every car that I drive. Carplay works just fine for my needs, and if any car brand has a better interface, good for them... but if they want me to even consider buying their product, they must provide me with an option to use Carplay. And if I used Android, I'd expect Android Auto. I am far more attached to the customized ecosystem I built around my phone and share with my wife, than to any specific car brand.