We took our defunct Dyson vacuum cleaner to the
The sample is too small for stats of course, but I've noticed before that people seem keen on chucking them out. We've had a few Dysons and I can't claim they were worth the extra money. They work fairly well and you don't have to buy bags, but ours didn't last any longer than previous non-Dyson cleaners and I'm not so sure about their performance.
Bags may loose their suction as they fill up, but I'm sure our Dysons have not given us a more dust-free house. We now have a Miele with a bag and so far it seems superior to the Dysons in that it actually does what a vacuum cleaner is supposed to do. It sucks up the dust and keeps it in that bag - all of it as far as one can tell.