Which DAC as a preamp?

Haven't heard the ones you mentioned, but I had a Bel Canto DAC3VB in my system and in addition to being a great sounding DAC I found its preamp section to be indistinguishable from my Bryston BP6 preamp.  There are a couple 3.5VBs for sale here now, one almost unbelievably cheap.  Read the reviews, and yes the VB version is definitely the one to get.  Best of luck. 

IME, Class D really benefits from a Class A input stage....solid state or valve. Unless you like that lean analytical sound. Many do. Good luck. 

Class D really benefits from a Class A input stage....solid state or valve.

All amps I know ss or tube have Class-A input stages, I've yet to see one with class-A/B

Cheers George

Check out the PSAudio Directstream DAC like others have already recommended here. Very good...

You don't say what your price range is, but I got a MSB Analog DAC with volume control and eliminated my preamp and the MSB is excellent.