In response to your question:
I have a friend who has an incredible stereo system.
(Avalon Eidolon speakers, ARC Ref. 1 preamp, Aesthetix Rhea phono preamp, VPI HRX TT, with Koetsu Urushi cartridge, and a Opus 21 cd player.) He and I have tried several tube mono blocks to augment his Classe CA401 (400wpc) SS amp. He tried the Kora Cosmos (100wpc), the Bat VK-150 (150wpc), the Manley Neo Classic 250 (250wpc) and the VTL MB-450's (450 wpc). (Lucky for me, I got to listen to them all!)
They all sounded great, but his speakers, like mine (I have the Revel Studios), are somewhat difficult to drive to realistic sound levels. This meant that all but the VTL's, did not have enough power to drive the speakers without clipping. (The Manleys almost made it, but they did clip, albeit gently, on a very large symphonic piece at very loud levels). Therefore, he settled on the VTL's.
Now, note the prices on these amplifiers, even used they are between $3,000 and $5,000 minimum. (Not counting the cost of retubing them, which is substantial). While I could afford that, maybe, I could not afford to do what he is doing, which is keep both his solid state amp and have his tube amps. He needs to do this because we live in California, where is gets pretty hot. (Neither of us has air conditioning either. Our priorities are stereos, not creature comforts like AC!)
We did a fair amount of auditioning of these amps late at night, with the windows open. Nighttime temperatures was in the 60's. Except in his dedicated and rather large listening room, where after only a few hours of listening, the temperature reached the mid to upper 80's! We were both sweating pretty good. (Good thing we had cold beer on hand!) Anyway, he now uses the tube amps during normal to cool days and uses the solid state amp on warm to hot days.
Now, my house is even hotter than his, since I live on a mountain ridge with a southern exposure. I can not afford to install AC in my house (it is an older house, and it would cost a small fortune), and I don't have the money to own two sets of amps. Therefore, I have decided to keep my Mark Levinson No. 23 (200wpc) amp. It sounds great, but maybe not quite as good as his tube amps. But then again, I'll sacrafice that little bit of sonics for a 20 degree cooler listening enviroment.
I know, this was a rather long winded response, but now you know the reasons I keep my SS amp, rather than switching to tubes. (Besides, to be perfectly honest, I was not dissatisfied with the Levinson amp, I merely wanted a change. I'm sure you know how that goes!)