Upgrade Bluesound DAC or go to Aurrender?

I want to go up a good step in SQ, I listen mostly to my Bluesound Vault2 and LP’s, streaming only for background music. Do I get a outboard DAC for the Bluesound ($3-5k) or switch to an Aurrender like the A10? Vote here. 
The Lumin T2 may sound better in your system if you go that route. I had an A10 and a Lumin T2 at the same time. The Lumin T2 would kick the Aurender ass 7 out of 10 songs but in my system it would get fatiguing. But in the right system it would be the choice. I moved on from them to a Cary DMS 600 which beats them both pretty handily. Just moved to the Cary DMS 700 which is another level in performance but with a price 
The DMS 600 will be on Audiogon tomorrow. Really nice all in one. 

Ask anyone if they like their $2000 or $5000 or $10,000 item of any high-tech category, and 90% of time they'll say how great it is, UNLESS OF COURSE, they've already decided to dump it.  The above discussion is nearly pointless.  I've conducted blind listening tests between Blue Sound and streamers costing 8x the amount of the Blue Sound.  If you use the same external DAC in the test, no one can consistently pick better than 50/50 a $5000 streamer over a $600 Blue Sound. Audiophiles like to believe they have golden ears.  However, the differences between an inexpensive and more expensive streamer, when using a high quality DAC, are always going to be negligible.  OR put another way, digital differences will never be as discernible in scope as the sonic differences between analog gear.

The one caveat may be the noise floor associated with a power supply comparison between streamers.  However, hook up an S-Booster power supply to the Blue Sound Node 2i ($350 bucks??), and I'd challenge anyone to a sizable bet that you could not do better than 50/50 in selecting a $5000 steamer over a Node 2i.  The problem with the above argument is you are not comparing just streaming functionality, as you're being influenced by the superiority of the DACs built into some higher priced streamers.  

I am confused. I thought that the node 2i takes a direct AC input. The S booster is a DC power supply. Please explain.