I am feeding the audio from the computer to my car radio (aux) so I usually only use the car's radio for that purpose.
I haven't had any problems with MC. I cant work the GPS feature, but thats my fault, not MC. I'd like it to be a little faster at loading the ID3 tags, and the mixer data, but other than that its an awesome program.
I pretty much only use Video and Music though. I just cant go a whole commute without a Britney video