Best high-efficiency speaker under 10K


I have never played in the high-eff speaker / low-powered amp space, but I've read so many things that I would like to give it a try. I own an EAR 859 integrated amplifier, De Paravicini's interpretation of SET. It's pretty incredible, especially if you consider its price tag. I am now in the business of choosing the right speaker. I listen to a lot of jazz and vocals and opera. So, I can do without the sub-40HZ frequency range. I would like to stay between $3K to $7K, certainly below $10K. Here are the options i am considering:

1) Zu Audio Essence.
2) Beauhorn Virtuoso (single driver)
3) KCS louspeakers (the model that uses the SEAS exotic driver)
4) Devore Gibbons 8
5) Living voice Avatar

If I had to choose right now, I'd go with the Beauhorn, but I know their limitations.

Any thoughts/personal experiences with the above or any other speakers in this range? Thanks.
ggavetti
If It were my money I would move KCS up to top position in your speaker hunt.
For the money you are wanting to shell out I think you would be hard to pressed to find better than one of JohnK's offerings from a bigger loudspeaker manufacturing concern.I have a pair of KCS Oris 150's bought as cheap as chips on here, the previous owner of my 150's I beleive had a pair of Avantgarde Trio's prior and I beleive he prefered the KCS 150's, and at a fraction of the cost new. I have personally not heard any of the Avantgarde range of speakers.
Gawdbless thanks for your suggestion. I haven't heard a single person criticize the KCS's, ever, which means they're really good. I have two extra-audio issues with them. First, I don't like their standard look (while many other speakers in this niche are prettier to my eyes). Second, I am not sure what their resale value is. From this standpoint, a more mainstream brand should be a safer bet.
I would suggest building your own, I just did it and could not be happier. There is a designer and a cabinet builder I can put you in touch with. Here is the designers site, mine are pictured through the link.

http://www.clearwaveloudspeaker.com/Symphonia/Symphonia72.html

These are my actual speakers driven easily with 30 watts.
Ggavetti, I can understand where you are coming from, but for me personally a speaker is a speaker and they ain't pretty,lol. I would go for sound quality everytime rather than the look of a speaker, or its resale value on the used market, I mean you could very well end up with something not as good as a speaker made with a personal touch just because it holds a better 2nd hand value than a non mass produced piece of kit?! If on the other hand you bought a 2nd hand pair for the price of a bag of chips you could/should be able to recoup what you paid if you decided they were not for you in the end. No loss. Result.
Then again there is always a plethora of reasonably priced lovely sounding gear on here, either way buying wisely should mean a lossless investment.
Let us know what route you decide to go.
You can never go wrong with Coincident Technologies. The Gallo 3.5 Reference at $6K is also excellent. The new Vaughn Cabernet at $8500 may be the best speaker south of $10K--heck, might be the best up to $15K.

Greg