With all that in the back where are they going to put the subwoofer?

.....or the dogs!

Doesn't it rather defeat the object of the exercise when the MP3 solution appears to take more room than the CDs it replaces, they could have done better with a lap top, and it would be less bothered about it being shaken about in the car.

As for the sun visor/keyboard - it seems to block out a great deal more useful information than the sun.