I have a Lenovo laptop [Z570] and I use Rdio to now listen to music via headphones. I have a MkIII Roksan Kandy amp which I would like to send the music from the laptop to. I've read in WHF reviews of many DAC's and quite like the sound of the AUDIOLAB M-DAC. Would I get a vast difference in sound quality if I was to spend 600 on this unit or would I be expecting too much from the quality of Rdio's music download service. Your thoughts pleeeeez.