Let's face it, tube audio isn't exactly cutting edge technology. There probably hasn't been anything truly groundbreaking circuit wise in any of our lifetimes. I believe Jim Marshall originally copied Leo Fenders designs, and before that Leo originally got most of his circuits from pre-war Westinghouse schematics.
Maybe I'm just nostalgic, but I figure anything Mr. Sundholm personally builds is a classic. Just like anything Jim Marshall, or Leo Fender personally built/would build is a classic. These before mentioned guys, and of course others; Dave Reeves, Dick Denney, Adolph Rickenbacker, and numerous others, are the original architects of musical instrument amplification as we now know it.
All building variations of very basic amp circuits, but each adding individual flavor to get the "ultimate tone" (or possibly to cut production costs, etc.), which by its very nature is as personal as someone’s taste in food, or the opposite sex, or the same sex, or whatever.
It's all about the mojo as far as I can tell.