I can confirm that DACS can sound different. The one in my Onkyo 7030 is warm and somewhat polite, If I go coax into my high end - ahem - Fosi Audio DAC 05 the sound becomes more clear with better highs.
I also just had a SMSR and Topping DAC in the five hundred buck range, and returned them both. No better than the Fosi 05.
Personally I would rather spend the money on records. They sound better and are just more fun for me.