So I've been driving a bunch of different rental cars over the past couple months, and it's time to compare Windows Phone bluetooth compatability between different manufacturers! (did I already do this? Either way, additional info here)
Worst: Kia Optima. Fairly straightforward to connect the phone, didn't drop any connections, but you have absolutely no control over the phone's music functionality from any controls on the car, whether on the steering wheel or on the car radio itself. The display also shows no information beyond "phone MP3" or something like that. Having to pull out the phone to skip a track was dangerous.
Problematic third place: Toyota Camry. The Toyota has some good info on it's display and it was easy to skip tracks from the steering wheel, but connections dropped quite frequently and sometimes would require a phone reboot to reconnect. It also confusingly has the ability to navigate through folders/albums/artists to select a song, but it selects ONLY that song. So it won't automatically go on to the next track, everything just stops when the song you selected finishes.
Meh second: Nissan Altima. Single line display on the radio, steering wheel controls worked, no connection problems. But no wow factor.
Winner: Honda! (might be biased because after renting all of the above ended up buying a Honda CR-V) It has a big display standard that displays the artist, album, track number, and title. The big surprise is that it can actually handle non-English characters! All of the Japanese album titles and artists showed up fine. I'll have to check if it will show contact names in Japanese too! Other than that, steering wheel controls work great, music starts playing on shuffle automatically as soon as you switch to bluetooth music (or start the car if it was already selected) and the connection has been great so far.
One problem with all of the above is that they all have their own voice navigation superseding that of the phone. So a special prize goes to the bluetooth FM adapter I bought for our old Subaru, which brought up the phone's voice command easily by holding down the call button. I wish I could get that on my Honda!
All tested with a 1520 running 8.0