Best DAC for under $500

I'm looking for a DAC with good transparency and dynamics. Is there a DAC with good bang for the buck in this price range that would offer a substantial improvement over a $1,000 CDP?
I've considered EAD DSP 7000 MK III and Audio Alchemy DDI pro but concerned about repairs.
So two other options are dAck $399 and the CI Audio VDA-1 $349