Actually the very same Butler as in car amps CWlondon
I bought a used 2250 to run my HT and I am very pleased with it. It is solid, has a lot of power and is very musical.
I won't try dazzle with some description of the perfect combination of tube and solid state blah-blah... I don't think that's what this unit is about.
In fact, it is decidedly non-tubish in many ways. The tubes are soldered in place - no tube rolling. They run blue not orange - thermionics. So the operating temperature is warm not hot - certainly nowhere near as warm as a Class A solid state amp.
As far as the thread mentioned above goes, I have never felt as though it overwhelmed the system. It went into an existing system and that's the way it has stayed. The differences were immediate and palpable. I liked it better so I kept it.
FWIW It has a good power cable, good power conditioning and sits on a 3" thick slab of myrtle.
What it does do well is handle uncompressed BluRay soundtracks. And it really kicks butt on 2 channel music since I biamped the mains. I think its an honest 150w.