Quiet and functions well ... but a bear to install due to design flaws.
The housing for this product had to have been designed by a novice -- fresh out of high school.
1. The removable duct connector on the housing is *exactly* 4 inches.
The rigid duct in the bathroom ceiling was also *exactly 4 inches, so the two could not be directly connected to each other without purchasing an extra part that cost more than $10 (up to $18, if I bought it at Home Depot) to connect the 2 ducts together. If the removable duct connector on the fan housing had been tapered so that it narrowed down to 3-7/8 or 3-3/4 inch at the smallest diameter, it would have saved me hours of going to multiple hardware stores searching for an unnecessary part.
2. The metal housing contains holes for nailing or screwing the housing to a wooden board in the ceiling or wall. My problem was that for the removable duct connector to be pointed towards my existing rigid duct, the part of the housing that would be against the 2x6 in my ceiling did not have any nail/screw holes on that side. So I had to drill my own holes in the *very* hard housing's metal. So what's the big deal ? That same part of the housing had other "holes", sort of like large grill work. These slots were covered up with a sticker giving some kind of warning, I think -- I don't remember any more. These long slots were way too big to use as a screw hole, so I had to find somewhere else on that side where my drill could still reach in to drill 2 or 3 holes. Not an easy task, and I was forced to choose spots close to the edges yet fairly close to the main opening. Once I drilled the holes, there was a protrusion on the inside of the housing that interfered with my screwdriver, so it took me about 20 minutes or more to screw in each screw, turning the screwdriver only 1/16th of a turn at a time.
3. The orientation of the grill cover does not match the orientation of the housing.
By this I mean that the long side of the grill cover goes across the shorter side of the housing, and the design of the grill-to-housing connectors do not allow one to choose which way the grill is connected. I was careful to order this product only after I confirmed that the dimensions of the grill would cover the same sized grill of the previous fan. (The previous home owner had painted the ceiling and the old fan's grill left an ugly dent into the paint and ceiling wallboard, and I wanted the new grill to cover up this ugliness.) Since I was forced to install it so the fan's duct connector was pointed towards the existing rigid duct, I couldn't just rotate the housing 90 degrees. It took me a couple extra days to sand, spackel, sand, spackle, sand and paint the ceiling around the hole for the fan.
Once I did all of this extra work to get it installed, it worked fine and it is quiet enough. I have no complaints with its function and operation.
I would recommend it to anyone doing *NEW* construction. If you are replacing some other previous fan, check your requirements -- including the fan's orientation with respect to any existing duct, hole size, and wooden beams -- very carefully.
Otherwise a 2 hour project could turn into a week long project.