I DIY'ed the official Carplay/AA install on my 2017 Mazda3. It's functioning fine, but I have a few thoughts after a couple months of user experience if you will allow me to rant.
Basically Carplay is an improvement over the original infotainment but implementation in the MZD connect system is miles behind what I've experienced in other systems. In both Kia/Hyundai and Ford systems I've used personally, the loading times and responsiveness is orders of magnitude better than with MZD such that as soon as I connect the iphone to USB, it is instantaneously ready to go. In my Mazda, both the system load time after starting the car and lag time for Carplay to initiate after USB connection is painfully laggy.
Also, Carplay UI really functions best with full touchscreen integration. Touch lockout when car is moving is annoying. And I don't agree with the safety excuse... trying to navigate the functions with rotary knob is not intuitive on many apps and takes my eyes off the road MUCH longer than being able to quickly tap the screen. Also, even when car is at a stop, touch function is limited compared to other Carplay systems (for example, you cannot pan/zoom maps or scroll through lists by dragging).
While I don't regret doing the install, I've realized not all Carplay systems are created equal. Using it in a recent Kia rental was a revelation. Improved usability from the snappy connection/load speeds and full touch functions cannot be overstated.
Thoughts or advice? Agree or disagree?