If you area DIY'er, you can match or exceed the empeg in most areas with a custom in-car computer. Specifically, you can get loads of hard drive capacity, great quality sound, VGA display, navigation, and fast transfer solutions including ethernet (including wireless), USB2 and firewire.

The negatives are that it's not as removable (although parts of it can be), and the user interfaces, while improving, are still rudimentary compared to the empeg featureset. There are some nice things that are available like touchscreens though.

Don't get me wrong, I'm still an empeg loyalist, because the software and community trumps all. That said, I've seen some spectacular carputer installs in the mp3car.com forums (as well as a lot of crap) so I'm just throwing that out there as a viable option. Be prepared for a lot of work and a much larger investment if you go that route though.