I have absolutely no complaints about the Menalux bags. They fulfill their function to 100%, thus there are 5 star.
I do not know what materials or other characteristics to justify except for the logo of the vacuum cleaner manufacturer the price of the bags in the original boxes.
The density of the pores would be an important factor for me. My very sensitive nose anyway that responds immediately to the slightest unpleasant concentrations of particles in the air, reports while vacuuming with Menalux bags no problem. Even if provided with Logo Products should be a bit better here, justified the not the huge price difference, especially since even his Menalux also do not deliver at cost price.