I just obtained a pair of Sonist Concerto 4's from Jonny at Snake River Audio, and they are among the best speakers I've owned. There are three sizes of the Concerto available, the 4's being the largest. They were originally designed to be used with a 300B SET amp, but will work well with any tube amp or integrated. I believe they are 98db speakers so they won't need much amp power to work at decent listing levels. The Concerto 4's retail for around $5000. So far, they are the best speakers I've heard in that price range.
