Fabulous! For my small room (approx 12'x12'), with the Classik speakers and two Kans (so 3 Uniks, 2 Kans and the Afekt subwoofer), it has more than enough grunt to scare me rigid at times. The power goes way up without noticable distortion (apart from the walls and floor shaking).
I gambled with the seemingly high price having read so many glowing reviews, but now I think this tiny box of magic is worth every penny (mind you, I got a discount price).