I did not realize how many times you have to change the motor filter / should - if one does not use the original bag. Since I started using Siemens / Bosch original bag, motor filter looks much better (after a few months of use). Under Swirl the last was turning gray after a few weeks. I am now convinced that I'm better off with original bags, and then not every year or half a year have to change the motor filter and HEPA filter. It must be said that I wg. Allergy to sucker often use. The Beuteil fit perfectly in my vacuum cleaner Siemens VS06, sit firmly in the holder and can be closed very well from the perspective of a dust allergy sufferer, when changing the bag.