I have a pair of AB2S monitors in my HT, as well as an AB2M-C centre channel. I'm driving the pair of monitors with my 4B SST and the centre channel with a bi-amped config from my 9B. My room is fairly large (13.5'x20'), and acoustically treated, with quite a bit of low-end damping and my major reflection points are treated with fibreglass panels. Accordingly, I have to turn the volume up quite high to really make the AB2's sound alive. But, when you give them the power they want, they reward you quite well for it. I can easily get 95dB at my listening position, about 10 feet away, which is more than enough volume for me.
As for midband finesse, I listen to quite a bit of progressive metal, a lot of female jazz, and quite a bit of small classical accompanyments with instruments like cellos and violins. I am constantly impressed with how well the AB2s perform im this type of environment.
I'm not sure where you live, but you'd always be welcome to pop in and have a listen should you be in my neck of the woods.
Jason
A photo of the system, from one of the rows of seats in the room:
http://malhavoc.homeunix.com/ht/final/fin_screen.jpg