I fully agree.
Some reviewers have badly explained the results of low powered sets, and in any case they will not satisfy heavy rock/metal lovers. They just have the greatest purity and enough sound pressure for pleasurable home listening.
My 8watts 300B SET plays on not even horn and not even efficient speakers (marvelous 88dB XTZ Master M2 speakers to hear or have), and yet sounds loud enough. Imagine now with efficient speakers!!! We, family and friends, are continuously marveled by the fabulous tones, dynamics and musicality. Every sound aspect is absolutely close to perfect. It is rare to be continuously satisfied, every time i power it up. Never had this with any of the SS system i had before.
One small advice, when choosing class A low powered SET amps, one must look out for the power supply; there must be a lot of it and of good quality. It is what makes the difference, especially in dynamics and output level.