what is the best, least costly DAC...?

I haven't heard the V-DAC with a PSU, only without one. If you like what the Saturn does, I highly doubt you'll be a V-DAC fan. The V-DAC sounds very dull and lifeless to my ears. It does the hifi stuff, but I view it as Musical Fatality, along with the rest of their gear.

I know it has it's fans. People rave about it and say it betters stuff that's 10x more money. I have no idea what they're listening to that the V-DAC is trouncing it. It's good for $299. It is in no way shape or form better than a Saturn. Not even close.

My Theta Cobalt 307 from around '96 beat up on a V-DAC in my system.

Everyone's ears and systems are different. Everyone likes what they like. I'm sure some people will strongly object to what I've said. Just my experience with it. Take it as you will.

To add...

Rega is releasing a DAC soon that is rumored to be better than the Saturn. Preliminary price is $995. Google Audio T Rega DAC for specs, pics, etc.

Srosenberg,
Please tell me about your Wyred DAC.
I am just about to spring for a Minerva and I am really very curious.
What did your ears find out ?
Regards,
Kerouac

If your V-DAC sounds dull and lifeless then I would suspect the digital cable or transport. I admit that it makes little sense to use a $1700 digital cable[Transparent Reference] with a $300 DAC but it works for me. I have found that the cable makes a very considerable difference. HIFICRITIC has tested both the Saturn and the V-DAC, they gave the Rega a score of 29 and the V-DAC 42. For comparison the Benchmark DAC scored 22, the V-DAC got just about the same score as a very expensive DAC from MSB which is close to $10000. They think it is one of the best buys in audio.

So you've had the RAM mods (including the Audio Consulting output Transformers ?)
All you now need is the Vacuum State Terra Firma Lite co-designed by Custom Analogue Audio.... this along with some other enhancements installed by CAA transformed my Saturn by an order of magnitude.
Forget the V-Dac and most others of even 8 times the price, the dual Wolfson 8740 dacs in the Saturn are damn excellent, they just need a PROPER PS and clock PS to really let you hear what they are capable of !

http://www.customanalogue.com/terra_firma_reviews.htm

http://www.customanalogue.com/terra_firma.htm#Terra%20Firma%20Player%20Upgrade%20Description

http://www.vacuumstate.com/fileupload/VSE_Clock_Upgrade.doc.pdf