Noise might be a concern if it is under a stand in the middle of your living area but mine is in a remote sump in a utlity room so any noise is not an issue for me. Honestly though my return pump is louder than my RS135... the only anoying noise is the sucking from the airline.

That's the noise they're all complaining about. :biggrin: However, I'm more concerned about the pump not being a particularly good match for the skimmer. The RS100 is seeming to outperform the RS135 on the same tank. Needless to say, the RS135 is still a great skimmer, just not as good as it could be with a different pump. ;)

Still looking.