Postive or Negative Results -Big Amp & Conditioner

I would like to take a poll on personal results with a big power amp. like a (Threshold SA/4e or Pass 350.5)plugged into a line conditoner/surge protection. If the results were good or bad. Meaning sound diminish. Or is it worth the loss of sound for protection of your power amp.

I have not yet tried a good line conditioner/surge protector on my power amps. Currently plugging directly into the wall.

So my vote is yet undecided.

Good -X ?
Bad -X ?

Be sure to give an explanation and or recommendation. No puny power amp apply. Just looking amps that have tremendous current that make your lights dim when turned on.
Thanks.
Joe