Those D700's are looking great and are highly regarded. I don't know much about bi-amping, but isn't the usual thing to do to use SS for the low end and tubes for mid and up?
Picked up the Tannoy Ardens this weekend. WOW.
Verrrrry sweet. And if you ever get the bug and want to go "more vintage." You can recone the HPD's, which btw I think sound really good, with a Monitor Gold kit and have MG 15's "on the cheap." In any event nice going. There is nothing like a Tannoy DC. Oh and one other thing you might want to think about down the road is a larger, folded horn cabinet. DC's like a lot of cabinet volume to get the max performance out of them. But if and until then, enjoy!!!
@Hawkeye83 time to build some Westminster cabs! I think I have the plans laying around somewhere.