My wife used to work for a ServiceMaster franchise, which means she was a professional vacuum cleaner operator.  They tried the Orick's and could not keep them together In fact, if you want a long discussion (ie: you listen while she talks) just mention Orick vac's.

I've not found a vacuum yet I really liked.  I did see one online the other day that was a "robot" of some kind.  You just turned it on and it wandered around the floor until everything was vac'd.  I have my doubts.