We've had our Dyson for a couple of months and I always have people ask me if it is worth the money. Up until today I had never performed a side-by-side test with our Hoover Wind Tunnel V2. It's a couple of years old and it was a little over $200 when we bought it. So, it's not a shabby vacuum at all. It also has the "powered hand tool" that spins a brush which is useful for getting animal hair up (we have two cats). This worked pretty good, but it was nowhere near the effectiveness of the normal Dyson attachment meant for upholstery. There is no reason for us to buy the Dyson rotating hand tool.
We have a bonus room over the garage that we have never used the Dyson in. I decided to use our Hoover and then try the Dyson. We have an almost brand new filter in the Hoover and the bagless collection area was nearly clean when I performed this test. The Dyson's collection chamber was completely cleaned out. Notice the amount of fur/dirt it picked up after vacuuming with the Hoover - and the floor looked clean after using the Hoover!
Results With Hoover
Results With Dyson