The tape out is a fixed line-level output, so the downstream amp will have to be an integrated or you'll need a pre.
Biwired from the Ayre terminals to Vandersteen is a bit tricky (I have the AX-5 Twenty / 3A Sigs) but doable. It's actually recommended in the 3A Sig manual to biwire this way anyway,
I agree the Ayre is a major step up. My dealer let me borrow it while the AX-5 was back in Boulder getting the Twenty update. I was very impressed.
No matter the price, Ayre seems to make top notch gear.