The T9 is a great deal if you are willing to fiddle with it on a daily basis when it acts up. I can't be doing that and driving. So after a month of it being installed, and 3-4 times of removing it and fixing crap and reinstalling, I finally yanked it out for the last time and put the stock unit back in.

1. Whine noise
2. Reboot issues
3. Backup Camera doesn't always activate.
4. Loses radio stations sometimes.
5. Volume control going up just one digit 2 to 3 is a large increase.
6. Doesn't have enough extra power to charge your phone with USB when using it for car play.
7. Weak cellular, wifi and fm station signals even with a stronger/larger antenna.
8. Fitment issues still around the vents. They do not fit completely flush like the factory did.
9. Two versions behind on Android.
10. Can't auto connect to hotspot on phones, so every time requires you do manually connect it.

Probably more, but these were my biggest complaints.