I read the FAQ on the website but it didn't quite go into the details as to what the wattage numbers mean and how they relate to impedance.

Say you have an amp that can provide 50 watts-per-channel at 8 ohms. This means that for a speaker with an impedance of 8 ohms, the amp can provide 50 watts of power (okay, I'm being redundat to make sure I understand things correctly).
From the faq, "low wattage amplifiers are the normal cause of speaker damage" . Just how much is "low wattage"? Say for example the M3, the max. amp power is 175Watts and it has 8 Ohms of impedanc - will an amp that can provide 50 watts of power be enough for that speaker? Can you ever have too much power?