Upgrade DAC/CD transport?

I have a Dodson audio DAC 217mk11D and am using a G&D transforms UTP 1 transport with Wywires digital coax cable connecting them. These components were very well reviewed approximately ten or so years ago and I primarily listen to CD's. I'm wondering if the newer DAC's would really yield much better sound quality?
Anyone have any experience with upgrading from comparable very good components from a decade or so ago?