I don't think these generalities apply at all, but if you want a very warm DAC, check out the ARC DAC 8 or 9.
Besides cost, I can't imagine a good reason to buy a DAC more than 5 years old right now. I _really_ love the DACs that have come out in the last few years at many price points, and I think they all really spank the previous generations, especially with Redbook.