This fan performs well. This is my second fan of this model. The first one is mounted under the floor in the downstairs cloakroom and is drawing air from 2 places, one inlet in the shower and one the other end of the room.
Timer set for 15 minutes. No moisture and no smells left after that time.
The outlet duct is 5 metres long and and changes from 100mm round to 225 flat before exiting through the wall.
The 2 inlet ducts are 2.5 metres each. one is 100mm round the other is 225 flat changing to 100mm round. at a T piece.
Excellent fan, you cannot ask for more, the fan still works well even with a complicated duct arrangement.