Miele is a premium brand. That means you pay for what you get. I usually buy expensive Miele bags for my C3, but they were too tempting to pass up. They're not as "beautiful" as the official bags, and as some other reviewers have pointed out, they're not exactly the same size. But they are also much cheaper. Unless you are asthmatic or allergic, I really don't think they will be that different (other than size). But since they have a sluggish production (maybe!), it's better you get the official ones if that's the case. For the rest of us, I think they work just as well.
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