Anyone using a Samsung Galaxy Avant (or other KitKat Galaxy)?

I've got a Samsung Galaxy Light, and aside from early-on phonebooth sync problems (solved with 3rd party app), it's been working quite well with my Prius. Entune apps in particular seem much more stable than they were with my old HTC. Now I'm considering upgrading to the Galaxy Avant, and wondering if there are any compatibility issues with it - I believe it comes with KitKat installed. My car has the Display audio with Nav + Entune. Toyota's compatibility checker so far shows Avant as working for audio and phone, but untested for the Entune stuff.

BTW, the Galaxy Light/Avant seem to be fairly similar software-wise to their big sibling Galaxy's - so reports from other Galaxy owners would be helpful too. I've read a few posts by people who had Prius problems after upgrading to KitKat, but I'm not sure if phones that come with KitKat installed are having issues or not.