I had my first listen to a set of 800 series speakers a couple weeks ago as I was buying a pair of 683's off a guy who had used them, occasionally, as rears, in a second system. His main system was amazing, to me, I must admit. With 802's up front, and 804's covering the rears. The fronts were powered by Classe monoblocks controlled from a Naim Processor of some sort. Sounded absolutely immense. Especially at volume. Properly amazing.
I clearly have nothing to add here, other than I heard similar speakers powered with a couple Classe amps, and it blew me away. Made me wonder what I would need to get the best from my 683's, as I doubt my 7 year old Onkyo 609 is doing them any justice at all, ha ha.