I always thought Dyson was crap, based solely on their obnoxious ads and garish design. Then I bought my wife their cordless upright vacuum for her birthday (I know, I know, but she asked for it). I was astonished when the vacuum became my favorite piece of tech in the whole house. We have a roomba that works fine, but it's extremely hard to imagine that I won't buy this thing immediately.
There was a recent reddit AMA by a vacuum repair guy, talking about the best brands: http://www.reddit.com/r/IAmA/comments/1pe2bd He was not impressed with dysons: http://www.reddit.com/r/IAmA/comments/1pe2bd/iama_vacuum_rep... I have to say in my experience, having had 2 dysons - they both broke within 2 years.
Of course the plural of anecdote is not data.