Personally, I love Dyson vacuums. Not every model, but the concept. I owned the VERY FIRST Dyson vacuum in the United States. I have the largest private collection of Dysons. James gives me one of every new model he makes, and has done so for years.
That being said, I find faults in his cleaners, as I can do with any vacuum. But I celebrate the great things. Like it or not, he's changed vacuum history, which is something I try to do with every engineering meeting they hold at the Museum. I also get to test every new model, finding flaws before the models get the injection molding made. Our current Maytag models are examples of two years of testing, and our newest "Jiffy maid" bagless upright went through over 13 redesigns before we 'got it right'.
By the way, I rarely sell a Tandem Air upright. I prefer the 7850 model, and think it's the most powerful, best clean air designed upright made today. Too bad it's going to be obsolete when the new Maytag models launch at the end of September, but the new Maytag clean air upright uses the double fan, double ball bearing motor and is definitely an improvement over the 7850 so I'm super stoked to see it launch.