Slanted Air extractor fans

[Keenoonvino]

Have posted this in Property with no answers so thought I'd try here!:

I have seen those angled air extractor fans a lot recently. I think they look quite good, and the benefit is that they are less imposing on the room.
BUT.... If I look under my air extractor now, it is so gross. Loads of grease and mankiness. If I get one where the bottom is basically on show, won't it look really dirty very quickly? Will I just have to clean it more? Sigh....