See update below. As others have said, the side vent will scatter light material unless you use a right-to-left sweep pattern - can probably be solved by gluing a small cardboard reflector to the side of the device and the filter pops easily to clean. Sweep pattern down. Update: I added a fourth star after a small modification - I glued a cardboard baffle so it doesn't get in the way next to the area you want to vacuum (see photos). Much happier now. In fact, for the price, this thing is great (now)! And with attachments for car cleaning, it becomes even more valuable.