I'm also in the market for a new head unit, but with a certain budget. The DDX814 head unit died one day after the car came back from the body shop. The unit looks good, and sounds pretty good, but was terrible overall. The UI wasn't so great, was slow, and USB file system was slow and limited (< 256 songs per folder).
I'm currently debating on a few models:
JVC KW-R900BT; No frills, simple, fast, and sounds great for the money. It has a 24-bit TI Burr Brown DAC. Looks like a toy boombox.
Kenwood DDX770 or DDX790; These models look identical, but it seems like the 790 reviews indicate it has better sound quality despite both having a non-specific 24-bit DAC. Too many bells 'n whistles, and I'm still scarred by the DDX814 experience.
That's pretty much it for now. I spent almost $1200 on my last head unit after taxes, and it's not something I want to do anymore. So something under $500 is plenty.
All I want to do is plug in a large capacity USB stick and enjoy good quality audio on my 2.1ch setup. Heck, I even thought about a Raspberry Pi project with a high quality USB DAC. [shrugs]
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