There is no such thing as a speaker needing power. Speakers don't need any power at all. Listeners do. Its you that needs the power, and the louder you like your music the more power you need. Regardless of the speaker, or its sensitivity, or any of that.
Regarding power, the one question you need to really ask yourself is: If the first watt isn't any good, why would you want 200 more of them?
Regarding power, the one question you need to really ask yourself is: If the first watt isn't any good, why would you want 200 more of them?