Musical Fidelity V-DAC vs. Spitfire/Supplier Duo


I'm looking to try and upgrade Redbook listening using my Oppo BDP-83 as a transport. I'm on limited funds and am considering two options as of yet. Musical Fidelity's V-DAC or the Spitfire/Supplier Duo. I've read good reviews of the V-DAC, but I'm hesitant about the "wall wort" power supply. Specs on the Spitfire/Supplier Duo look promising and I like the beefier power supply option, just not sure about quality.
Am I placing too much of an emphasis on the power supply of the V-DAC? Or am I tossing dollars to the wind at this price point to try and improve the Oppo's stereo listening?
Thanks for any input and hopefully, personal experience with either of these DACs.
powerwindow
According to a test in the current HIFICRITIC the V-DAC outperformed several others including the Cambridge Audio and the Benchmark DAC1 Pre (42 to 24 in their scoring system. I have found specs almost totally useless as the better companies are always conservative and the worse companies exaggerate shamelessly. Apparently the wall plug did not have a serious effect, they recommend the V-DAC highly and as they take no ads they have no motive not to be accurate.
Stanwal, I could not read the review online, but assume it was the article relating to the 6 DACs. It seemed it was geared toward computer sound systems. Does it seem the V-DAC could still be promising for an external DAC w/ my Oppo BDP-83?