I have always had the thinking that one you fit to the ceiling wall or floor will not be as good as one you fit to your face so always make sure the face one is just as good if not better than the one on the floor wall ceiling, Just my way of thinking I spose. I only have a little 10x8 summerhouse turned into workshop so space is at a premium I therefore use a dust extractor in a shed next door and have a pipe running into shop which i put on the item I use which is of course mainly the scroll saw lol. However if there is a little unit in the uk that would also clean the air when I leave and am in there please let me know as I am an acute asthmatic so its always better to air on the side of caution as it is I sound like darth vader when i say yes to a cup of tea from the missus whats one more noise in the background when you are making dust.