In Germany EUR 450,- for a pair (matched, obviously).
Ignore those exact figures for a moment. I bought them for my EUR 2.2k Unison S2K, a very big leap of faith indeed. But one I have never remotely regretted from the first moment on. Can it compete with a 20k amp now? Don't know, but it sure has become another amp, definitely better in every respect (you're spot on:"sing" is indeed what it does).