I have concluded that lower power versions of the same circuit sound better than those iterations with higher power if the power is sufficient to play at a volume you are satisfied with in the room you are using. If we know the watts, the speaker sensitivity, the impedance profile of the speaker, the room size, and the average dbs you listen to in your listening position we can probably guess if the amp is powerful enough - though that does not replace actually listing to it in your room, but a guideline at least. I know that for my speakers, 30-40 tube watts are more than sufficient under almost any circumstances in my 18x12 room - more power would require more amp complexity, and that just never makes sense to me when less power does the job. I've had tube amps from 27 watts to 162 watts, and for my listening it seems power was simply not relevant above 27 watts - and lucky since that lets me listing to EL84 tubes.