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

I agree with the poster that you should head to one of the audio shows to hear many expensive speakers, which is the rule at such shows.  However, in my experience, and I have had a number of really expensive speakers, you should try some of the single-driver speakers.  I bought a pair of Audio Nirvana 12 inch alnico drivers and mounted them in a 5.6 liter cabinet (I also had some 8 inchers in a 2.8 liter cabinet).  These cost me about $1500 and I will never (as much as any of us audio nerds can say never) go back to multi-driver speakers with electronic crossovers.  Just a thought before you did like I did and spend a lot of money chasing what to me doesn't sound like live music.  My kids and wife all play musical instruments.  An added bonus is that these things are really easy to drive due to high sensitivity and a more resistive load.

Some diverse and excellent suggestions, here.

If you're interested, a system that, ime, sounds terrific -- are these: http://www.grimmaudio.com/hifi-product/loudspeakers/ls1/
with these: http://www.grimmaudio.com/hifi-products/loudspeakers/ls1s/

Best of luck,

Sam

Indeed, all good ideas. Remember that the retailer's middle-man will have tweeked everything to perfection, which you won't be able to reproduce in your living room, plus you're parting with twice the money the retailer paid for them. I hate to sound like a broken record, too, but investigate Tyler Acoustics in Kentucky.

I was recently making just this sort of choice.  I finally opted for Wilsons, but the Maggie 20.7 were my runners up. (I'm a sucker for clean low bass)

Large Advents for sure because you just never see them at that price.