James Dyson's claims are rubbish, what is wrong with the German companies quoting their empty bag figures? Nothing of course, that is how the cleaners are supplied to consumers and they can change the bags as often as they wish.
He is equally misleading about the pad filters in such as the Vax cleaners. I bought one of the Vax Air cleaners and at £250 it wasn't cheaper. I bought it because it was better than Dyson's offerings in many respects and remains so in practical use.
And his current spiel about an up to 110,000 rpm motor is also nonsensical, since its speed is not to improve the performance, it merely compensates for the undersize diameter air impeller the miniaturised cleaner has.
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