Very loud.  I mean VERY LOUD!  Still not working yet as it blows air in rather than removing air.  Disappointed.  Costing me a fortune in HVAC, electrical & kitchen installer fees and it still doesn’t work.  My installer said it was the most complicated install into a custom hood ever,  Sadly can’t recommend.
Update: turned out to be HVAC installer problem, so yup I like it, it is quieter now.  Over all very complicated for the trades involved.