Miele. I just got the Consumer Guide vacuum report and it recommends several models of the Sears Kenmore machines. But reading on the Sears website, the reviews are mixed on them. And don't forget, we all have different dirt and different STANDARDS, too. Personally, I hate bagless, but some don't mind.
Check Craigslist and you will see the ones people don't like!! Very seldom a Miele on there....mostly cheap uprights, and lots of Kirby's.
Another thing to consider is the cost of bags. Miele now charges $19 plus tax for 4 bags!!!!! I buy the generic ones on Amazon. With a small farm, cats and a wood stove I change bags frequently.
Dyson's may be fine on cat hair, but they don't do well on litter. A friend had the best Dyson makes and she has litter bits all over her house. The machine sucked it up but spewed some of out again.