My Dyson 04 (yes, that old) finally gave up so I was in the market for a new cleaner. Definitely not a Dyson though, I'm just not convinced that spending more than £200+ for most models will give a vastly superior service to something costing a £100 or less.
Reading the reviews for Hoover, Vax, Zanussi and Samsung, especially the one star ones (some customers seem to have remarkably unrealistic expectations of what a vacuum cleaner will do) and considering the price I settled for the Samsung SU3350.
So far, after a few weeks, it does what it's supposed to do. It has a very long cable, good suction, height adjustment for different floor surfaces, very convenient to empty the dust bin and light enough to carry easily (unlike the heavy Dyson I had). The only drawback I've found is the suction hose, this is spring wire with plastic covering and when fully extended it naturally wants to contract and because the unit is quite light it could easily pull it over when cleaning stairs or in corners (so I've knocked off a star).
A minor tip should you buy one: the power cable comes out of the machine quite low down, so you have to pick it up first. I suggest threading it through the handle. This way you can use the machine from switch-on without worrying about the cable on the floor near the unit.
For the price I'm satisfied with this Samsung and even it if doesn't last for years, buying another one (or two) will still be cheaper than a Dyson.