Is it worth spending $10k on CD-only player today?

Spending 10k on a redbook cd player only would be very very hard for me. Unless it just sounds killer and can beat something like a Esoteric UX-1 which does all.

I just bought a Esoteric DV 50 ($5500 new) SACD-DVD-DVD-a and I have to say I'm pretty amazed. I'm not sure there is a significantly better redbook only player at this same price.

So, I got it all in one.

PS, my vinyl I still like better, but I now have access to some great music. SACD/redbook is pretty darn good though...

I'm not sure that it ever was.

In digital media sonic quality is ultimately limited by the finite amount of information on the disc. Playback equipment, no matter how good (or expensive) can only approach a limit imposed by the media. The information on a CD, 16 bits and 44.1 KHz sampling, is barely acceptable for audiophile recordings. The much greater information available on a DVD or SACD permits any decent DVD/SACD player to compete with the best CD players.

Presumably the answer to this question depends on the individual and their priorities. In my case the answer is yes, it is worth it to me. I want outstanding sound, in digital format, right now.

Not to me.

Yes. I would if I had the scratch, a larger income, or if I was more established in life. SACD isn't going anywhere unless you listen to classical music. I do, so I would likely consider the Meitner stack. I would not consider something with compromised redbook playback. I'd rather have a dedicated rebook player in that scenario. And I feel that is the crux of your question. Redbook is too ubiquitous. And as such would not fit morepeople's definition of 'obsolete.' Though there are many slight meanings of the word.

Although SACD and DSD is superior to redbook, redbook will likely be obsoleted by mp3 or something similar. And by something similar I mean something distributed as a computer file - either hi-rez (not likely) low-rez (more likely).