Absolutely no intention to preclude lower-price gears. It is just for such fine quality recordings are difficult to find online. I know, from the responses above, some gentlemen have their own perfect reason ditching the use and purpose of them and I respect that. I certainly understand the limitation and bunches of factors playing into that may invalidate legitimacy of using that avenue for selecting the hi-fi or mid-fi (if you judge them purely base on the price) gears. But I believe that is the dilemma that many audiophiles run into because of the limited resources around the neck of wood where they live. I certainly do not have much disposal money to purchase and bring all of gears I am interested home for auditioning. That is essentially the reason why some enthusiasts put out a fair amount of time doing so to help out and I appreciate that. The is apparently the suboptimal way given the reality constraint.
I also agree the blind test needs to be part of equation and you could do it in your discretion.
For those who are reluctant to admit there is diminishing returns, listen to what the humble gentleman Paul has to say: https://www.youtube.com/watch?v=a5GN1a5XmTU.
I also invite those who have DACs you think exceptional/worthwhile could also spend some time doing some fine recordings and showcasing your gears with the community. Would you? Appreciated.