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
Phalen, (others) Musical Affairs Grand Crescendo's. We listened to PC music source through a Leben CS-660 integrated 22 watt amplifier, which is really nice itself, and provided more than enough umph! I'm not at all versed in giving reviews, but I can't imagine anyone with complimentary amplifiers etc, not being ultra satisfied with these! The only thing I didn't like about them....they weren't mine!
Vaughn Loudspeakers Zinfandel or the Cabernet. Absolutely fantastic full range high efficiency speakers with a benign load. Ideal for SET amps. Also works with any type of amps.
I am presently using the Zinfandel in my system driven by the Symphonic Line RG1 amp and the sound is gorgeous. It uses the fostex driver, ribbon tweeter and a 12" bass diver.
Thank you Isochrnism. I know that there is no substitution for an audition but one of the shortcomings that single driver speakers seem to be labeled with is that the do a relatively poor job of reproducing dynamics and complex passages. Did you listen to any challenging music e.g., large scale orchestra?
One of my friend's favorite references is Stravinsky Rite Of Spring w/ Valery Gergiev Kirkov Orchestra. I was VERY impressed, to say the least.