I recently bought a pair of Avalon Opus speakers, with ceramic mids and tweets and a dual 9" woofer system. Like many Avalons, they are known as a finicky speaker to get sounding right. They are easily the highest resolution speaker of the 250 or so pairs I've owned, which cuts both ways, of course.

I managed to get quite good sound with my modded NuPrime ST-10, but felt there was yet more to be extracted from the Opus. I was hoping for a little better woofer control and a bit smoother, less bright presentation from the mids on up. These speakers were developed with Spectral amps, which have 2mhz. bandwidth and prodigious damping. A friend has one, which I've admired.
Tommy's amps have a very wide bandwidth and high damping, and I thought the 60V version might have the cajones I wanted.
Today I got the King Maraschinos up and running, and they are everything I wanted and more.
What a g** d*** superb amp!
The Avalons are now singing like nothing I've heard in my home in my 49 years in the hobby.
Transparency, image depth, width and solidity, bottom end control. Beautiful detail, air, and delicacy on top. All aces. Perfect immediacy and astonishing detail, yet with notably less brightness and glare. The whole enchilada.
I noted Charlie_flowers above successfully used Maraschinos with MG3.7s, which is a damn tough test, as are the Opus. Same story.
I've probably owned 75 good amps over the years, too, and heard a great many more. Matchups tell the final tale, of course, but these little guys stand tall with anything I've heard at $10k or under, IMO, and would embarrass some higher priced units.
My simple advice if you are looking for a truly great amp that will do justice to even the finest speakers- just contact Tommy and try one. Pretty simple, no brain required.