Best dac under $2500 - comparing build quality and technologies

I have been in the  Audio field for over 4 decades and have owned some pretty exclusive audio gear 
I was listening to a 3 years old R2R dac the R7 from AudioGD a 20 year old company which won several awards  which is not known much in the U.S yet  ,This New R8-MK2 is better still.
it is  very well built using 3 R core transformers rarely seen unless spending $$. Their latest and best value is the New R8 mk2 dac. This dac just came out late April 2021 ,over a year went into the redesign the Owner stated this unit has several advancements vs previous designs , and runs much cooler for less money then  the previous R7 but better ,their is also a mk2 R7 also as well as a Flagship R7 HE with power regeneration,which I wanted but could not afford .The dynamics and realism is what sets this apart it’s massive power supplies and over 130k uf 
of capacitance is more then most amps has a lot to do with it I will be getting my dac next week and put side by side with  very well know competitors  it was noticeable better  in several areas , and it has 7 sonic adjustments all FPGA based 
4- non over sampling ,including a vinyl mode, and 3 over sampling  other dacs just a minor OS option 
you literally can Taylor the sound to your audio system .it weighs 26 lbs ,Underwood Wally is now the U.S distributor and service center  . I will give a full rundown once I have logged a week or two on it ,2 R- core transformers go to the pure class A  analog output section, the 3 rd transformer -digital is now fully servo controlled and runs much cooler and much better specifications . Check out link below.
http://www.audio-gd.com/R2R/R8mk2/R8mk2EN.htm