jvc avx77
I used the old AVX1 unit from JVC which was the very first one they had. It was a great unit and the only thing I wish it had that it didn't was a USB input. All the new ones have this option and bluetooth built in. Sound and tuning were very good with 5-volt RCA outs and a full EQ with sub controls.
It is as close to a double DIN you can get without all the customization. A regular harness, antenna, and mount adapter are all that is needed. It really looks different when it is lit up and running. The screen looks bigger then it seems. I've played with one a few times and installed 2. They are a very cool option.

