I've got the religion.
I built it, into a prototype at first, a really cheap RMS 2x8 combo cab.
I then felt confident enough to put it into a Sunn combo 112 that had been taking up space under my pool table. I went with a Weber Signature Ceramic 12". and I don't care what they say, this amp is like nothing I have ever played.
Tone? furgettaboutit...I'm not worthy! Sustain? It's there, so much that it sounds like there's reverb and phase shift that isn't plugged into the amp. I know most of you guys know what I'm describing...the only word I can think of is...sweet! It's just outstanding.
I built this one out of both spare parts I had around, and purchased the transformers form Weber. If it gets better than this, just call me ignorant and I'll march forward. But I can't possibly describe how good this amp sounds, even at low volume. It just sings!