The gable mount is the least invasive, least expensive and much much easier to install. Mine came from Lowes. Mine is mounted in a gable directly above my den and when it comes on we sometimes notice the sound unless the TV is on. It's the motor vibrating on the wood frame and not the air sound on the blades which you can hear from outside. I stapled cardboard to seal the remaining part of the gable so the air would have to come from the other end. I would mount it in the other gable at the other end of the house if I had it to do over again. It would be best to pull the air across the part of the attic you wanted cooled most first.