does more power=better quality ?

thanks for all the inputs.
i should elaborate more on my question.
let say if i use a bookshelf speaker ( revel m20 or bw 805). i get the impresseion from some post that lower / midpower sounds better than the higher power model ( within the same brand ) for example. some have say pass x250 sound better than the x350, or a krell 100 watts sound more sweet( whatever athat means ) than a 600watts krell amp ( again same company and same line product) i was comparing a sony receiver to a levinson amp.
i like to know is it true and why

correction
i mean i was NOT comparing sony to levinson amp

"there are fewer output devices to muck up the signal" is it kind of like thecar analogy.for the uninitiated ,non engineer . can you use the analogy of a car.just because you put V8 engine, the car may accelerate better but it doesn't always handle better. some peoplle may preferred a mini cooper vs a corvett because they feel the mini handle's better.

are all output transistors created equal.given the same manufacture, mode...etc do they all sound alike?
if not, is it possible to have just one output transistor?