The Weiss 204 is kind of an enigma in the sense there are a couple measurement based reviews which are negative and a couple subjective reviews which are very positive.
I purchased the 205 after reading the positive reviews and compared it to my Meitner MA3 which is way more expensive and differences were similar to what is mentioned in https://twitteringmachines.com/review-weiss-dac204/ where the reviewer compares it to his TotalDac. Basically, for the $$ I really like it. I've since added a Linear Power Supply to the 205 which was nice improvement, at least in terms of dynamics. I have no idea how it compares to an Accuphase DAC board. I like having the choice to swap/upgrade DACs as new 'popular/great-deal items' become available (regularly) so personally for me I wouldn't be interested in a DAC board as even if it's killer I know I would want to try different things... Used 204s show up in the $2700 range. Vintage King has a demo available as I'm writing this.