Hi Mike,
I run a Prizm skimmer in my sump, which is also in my bedroom along with my reef. As for noise levels, your always going to get some noise when you mix large amounts of air and water together. My Prizm does make some noise but that's only from the mixing, no pump noise-which is what pleases me.
It's not a bad skimmer, however my 27gl is
fully stocked so I think I need to upgrade. When I get a larger skimmer I know I'm going to have to pay the price of alittle more noise, thus more air and water to skim more volume.
Goodluck
cheers, Rich