I have also heard dacs sound different from each other. I even had an old dac upgraded and it became much better.
Regarding the question I would guess that something like a ML dac that was very advanced for its time still sounds good. Maybe not as good as the latest equally advanced and expensive dacs. If you can get it for a good price it may be worth it.
On the other hands there are now dacs for $1k - $2k that are said to sound great. You would probably have to compare the old and the new next to each other to hear which is best and which one you like the best.
Here is an example of a somewhat affordable dac:
https://www.stereophile.com/content/okto-dac8-stereo-da-processor
If you for some reason don't trust Stereophile it also got a great review at ASR
https://www.audiosciencereview.com/forum/index.php?threads/okto-dac8-stereo-dac-review.14705/
Regarding the question I would guess that something like a ML dac that was very advanced for its time still sounds good. Maybe not as good as the latest equally advanced and expensive dacs. If you can get it for a good price it may be worth it.
On the other hands there are now dacs for $1k - $2k that are said to sound great. You would probably have to compare the old and the new next to each other to hear which is best and which one you like the best.
Here is an example of a somewhat affordable dac:
https://www.stereophile.com/content/okto-dac8-stereo-da-processor
If you for some reason don't trust Stereophile it also got a great review at ASR
https://www.audiosciencereview.com/forum/index.php?threads/okto-dac8-stereo-dac-review.14705/