Product review (3 stars): Needs Some Headroom...
These work as an odor filter as long as they don't get clogged with grease vapors.
I also had a problem when I installed a new filter...there was a noise coming from the fan...turned out to be the fan dragging on the top of the filter.  After I removed the filter and made sure that the filter was bowed downward in the middle, the fan doesn't touch it anymore.  Maybe the manufacturer should allow more clearance between the fan and filter..