One good point that should be drawn from this banter is that all tube amps are not providing "real" tube overdrive. Many makers use the same kind of circuits used in distortion pedals to produce their lead channel's distortion. For the sake of that point, the phrase distortion and overdrive are kind of interchangeable because the lines have blurred. That still makes for a good sounding amp by the way, it's just a different way of achieving clipping.
One disappointing side effect to that type of lead channel is that a tube screamer style OD in front of the amp will not respond the same way it does with a true tube preamp. If you have a preamp stage with true tube OD, then the TS/OD pedal can just add grit, or with the output boosted too, it can push the tubes harder. That's a great sound. But if there's a solid state distortion circuit inside the amp that's just "flavored" by the preamp tubes, then the OD pedal in front of the amp can sound more flat and lifeless, because it's not pushing the preamp tubes, but rather stacking (cascading is an okay word I guess) two solid state OD/Dist circuits.
I feel like that's something you need to know before you buy a certain famous brand tube amp. Sound and feel are the ultimate judge, so if you like the amp, it matters not what preamp they're using. But if you're hoping to do the SRV-style setup with half grit on the amp and half drive on the Tube Screamer, you may get less dynamics from the solid state amp distortion. The Marshall JCM900 is a perfect example of this. But even that kind of amp can be great, because then your ideal setup could be running a tube OD pedal (V-twin, etc) in front of the amp. That way you can "cascade" that into the clean channel for the most organic sound, and still use the amp's lead channel for total saturation. In other words, it puts the tube OD on the floor, and the "SS distortion pedal" in the amp.
I like to think of everything in a modular way. I mean some amps are just built perfectly and you can't attribute the magic to the preamp, the OD, the power amp, tube rectifier, etc. It's a total sum of the parts. Everything is in harmony. But most of the time, if you know what you've got "under the hood" you can assemble a great rig out of anything. If you want classic high quality tube tone, it's kind of like this:
Got a JCM900? You need a V-twin or a H&K tubeman, etc.
Got a Recto? You need a TS9 or Boss Super Overdrive, etc.
Got a vintage Fender? You need a couple boutique OD's, one that totally saturates. Maybe even the Boss Metal Zone for full on metal.
Got a Crate/Peavey/etc. SS amp? You need a tube preamp. (then see "Got a recto?")
Got a POD? You need...well...therapy.