I'm planning to invest in a Hero3 Black edition soon for internal and external car stuff. The new Black edition has WiFi and a remote as standard so is more versatile than ever.
We use a Hero2 for follow shots when doing car reviews and it is hard to work out what you are seeing. Once I have the Hero3 I can mount it on the nose of my car and link it via the built in WiFi to my dash-mounted iPad so no more guesswork.
The quality is more than good enough and will probably replace my EOS 60D for in car review work.