I also bought a Dyson, but was never happy with it. It simply didn't have enough suction power, compared to what the commercials promise. Then I got a free Miele vacuum with the new Miele washing machine I bought. Love it. I wouln't trade it for anything, and if it breaks down, my next one will be a Miele again, for sure. Ok, it still uses bags, but I don't care about that. It gets the job done in the fastest possible way.

Only one brand of vacuum cleaners impressed me even more, and that was Kirby. But those don't even sell through the regular channels and they don't come cheap either... but you can find new ones on eBay for half the price. (honestly, they only thing stopping me from getting one of those is the price because they are just so incredibly good).