Dyson for me. I have had one for eight years and it is still going strong. It has given me a couple of scares over the years, but it has always come good.
Ten years ago when I was furnishing a flat with a flatmate, we spent a weekend spending a small fortune on furniture and fittings. At the end we were looking for a vacuum cleaner. Because we had spent so much money we baulked at a Dyson and went for a cheap model (I was a permie back then

).
The suction was so useless that you had to pull the machine around picking up the dirt from the floor with your fingers and then holding it over the end of the hose.
A cheap vacuum cleaner is a false economy.