I think there's something to making reissues of old HUs and/or making retro-looking ones with modern features that aren't just modeled after AM radios from '57 Chevys. I like that companies are doing this!
That said, this thread is timely, because I dragged out some old favorites while cleaning the garage. I have a small collection of vintage HUs. This isn't all of them, but some of my faves are here:
On the left is a Yamaha YCR-305 pull-out unit and a Kenwood EZ-500. The Yamaha was a $2 swap meet find, and the EZ-500 spent time in my 2002 WRX. On the right are two of my all-time favorites: the Alpine CDM-7871. I had these in my old '89 Maxima SE and my 1992 F150 Nite Flareside. They were incredible in their day, and look fantastic all lit up. They also have mechanical tilt faces for extra baller status.
Once I can get to the point where I can put a radio back in my Trans Am, I've got these, a late model full-logic Alpine cassette deck and an Alpine with iPod controls to choose from. I'm going to add Bluetooth as well through the Aux input on one of these.