What used speaker would you buy with $20,000-$35,000 and why?

Since hookers and coke evidently wasn't the right answer,

I'll add that a pair of MBL 101e are listed here at $20k.  They have certain strengths that are IMO just about SOTA, but they are omnis (a plus for some listeners, an issue for others) and the low end requires a large space IMO for proper tonal balance.  Personal taste is going to drive this decision, but hearing the 101e would be a useful bit of due diligence.  If you listen LOUD, I'd say that it's a "must hear".

Ctsooner,

That's a very tough question to answer. My understanding is that the 101 is power hungry and a tough load.  MBL says that MBL amplification is uniquely well suited to the speakers' demands.  (What else would you expect them to say, they're trying to sell MBL amps.)

I've heard the 101s at three different locations:

A stereophile show, where they were demoed by MBL
An MBL dealer in SoCal
A second MBL dealer in SoCal

The latter two were full line dealers who also carried MBL amps, preamps, CDPs, etc.. Guess what: all of those Demos featured MBL electronics throughout.  What a surprise!  The demos all sounded great (in many respects) so the chain certainly was appropriate.  However, it's also entirely possible that dozens of other brands might sound as good or better.  

I have no clue how other brands mate up, and I suspect that it may be tough to arrange a demo to check this idea out.  It's just not in anyone's interest (except the consumer), so I'm not sure that you can ever expect to make such an audition happen.  It's still worth a shot if you're thinking about an MBL speaker purchase, however.  Maybe you could haul your power amps to the local MBL dealer when auditioning MBL speakers, but given the weight of many high output power amps, that's probably going to be a chore.  (Hey, one more argument for class D)!

The MBL amps appear to be quality pieces, but cheap they ain't!  So, if you're up for the effort, you might want to try this one out and let all of us know how it went. I guess I'm just too old, tired, and lazy to be of help, here.  Sorry

Hookers and coke.

The "hookers and Coke" line was a reference to a recent Fox News attempt to play up the Lotto fantasy during a live interview.  You might want to "Google Fox News lotto interview hookers and Coke" if you get a second.   It's hilarious.