Well, I did an CCC to andriod head unit upgrade not long ago to my 05 645ci and here is the result:
you can tell even the bmw original screen has a better resolution, the total cost:
Headunit from Wakaa $339 and an AUX cable from amazon $8,
the reason I did it was ever since I got my iphone11 a few years ago, my blue tooth stop working... and I really want to use carplay so I can use maps from my phone. Keep in mind, I have NO AUX to start with, so it's a 2 step process...The only imperfection is that the music coming from the new unit is through AUX, which is only L/R, the sound quality is not as rich as original BMW (FM/CD etc), which I can still use with no problem.
In case you wonder, I didn't buy a backup camera($20 extra but lots of work routing the wire) since mine is a convertible, who needs that while I can turn my head
