I have owned so many Rectos. Couple Singles, a Rev F Dual, a Tremoverb, a couple other 2-channel Rev G Duals, a Rectoverb, a couple of 3-channels, a Roadster. I'm probably missing one or two.
Tremoverb was definitely my favorite, just sold it a few months ago. The Tverb hits like a fucking tsunami. Big, deep, inexorable. Playing lead on orange high gain or Blues was basically like cheating at guitar. Problem was if you play it as much as I did it breaks down a *lot*, as any 30-year-old amp will. Roadster was second just on insane versatility, tied with the Single which like people have mentioned is kind of a different amp. You've gotta put the Single through a 4x12 to really hang but if you do it's the best OSDM or hardcore amp ever. EL34s in it'll cut your head off, I actually found it too aggressive. Liked EL34s in the Roadster though.
Didn't like the Rectoverb. Had the wider gain sweep of the Tverb but without the massive power section, and didn't have the gnarly cut the Single does.
I didn't think the Rev F was anything special compared to the Tverb or Rev Gs, it cut a *little* better but you could just throw an EQ pedal in front, boost the upper mids a tiny bit and drop output volume a few db and you just saved yourself a few grand.
3-channels need a boost to chug hard unless you play real loud, but they're the perfect 'rhythm guitar' amp because the spectrum's so wide. you can carve so much out of that sound for the vocal or a lead and still have a ton of guitar in the mix.