Chadnliz, The Dakiom tweak is excellent when used in modest cost CD playback systems, which is how I use them. Others have used in very high end applications, too. There are many favorable comments on the website from Audiogon members, myself included.
Dakiom promotes a much more realistic, non-fatiguing sound, and allows a musical, three dimensional, quality to replace the less engaging sound in my unpretentious systems.
Also, as mentioned above, Ric Schultz at EVS is a great designer-modifier, but his truly amazing results will cost more. His older Millennium DAC's are still classics.
Don't forget to use a good quality digital interconnect if you go the MSB Link DAC upgrade route.