Pros: they are a little larger than the original Miele bags and fill the space inside the vacuum better, thus lasting longer between replacements.

Cons: the original miele bag have a stretch rubber gasket that totally sealed the neck of the intake tube when you shut the lid, but the filtrete bags only have a rigid foam gasket that is a little larger than the intake tube. this allowed fine dust to actually be sucked out of the bag and pretty much clogged the little rectangular shaped secondary filter with crud.

i was able to solve this problem by wrapping some rubber tape around the intake tube making the outside diameter larger so it fit snugly to the rigid foam gasket on the filtrete bag inlet. problem solved, but requires a slight modification to the inlet tube.

Other Thoughts: overall, i will probably continue buying the filtrete bags, the factory miele bags are ridiculously expensive and have recently gotten smaller than the original ones, obviously a marketing ploy by miele to make more profit from bag sales.