Great speakers! There's a nice VAC Sigma 160iSE available here (with extra tubes) now for $7500, which looks like half of retail so you can probably resell at little loss if for some reason she don't work out. Reason I'm recommending VAC is I believe that they have a reputation for handling bass very well for tubes, they're built like tanks, and are said to have very good customer service. Maybe read some reviews and see if you think it'd tickle your ivorys.
As a possibly useless aside, I got to hear top VAC, VTL, and Zanden electronics back to back driving Grand Utopia speakers. For my tastes VTL was a little to cold, Zanden a little too warm, but the VAC seemed juuuuuust right. All three designers were there for the demo, and in the Q+A afterwards Kevin Hayes was extremely impressive in the level of his knowledge and his ability to explain complex issues.
So, as a big fellow JA fan (I've heard just about all of'em) and hopeful future owner, if I was looking for an integrated I'd be leaning VAC's way hard if I couldn't audition in person. But, I'd more likely contact Don Sachs and have him build me one of his preamps and amps if I didn't absolutely need an integrated. Apparently his tube amps are something special, especially with how they handle bass. Just had to muddy the waters a bit. Heh heh. Best of luck in whatever you decide. BTW, what interconnects and cables are you using? Cardas?