I use Shark and Dyson. Dyson machines are great, but really check out each model before you buy. Some are very application specific. My Motörhead is great on hardwood and low pile carpets, but I wouldn’t use it to vacuum my whole house. (I use the DC65 for that.)
I use sharks in the restaurants because they get the shit beat out of them. They do a pretty good job for the money. I like them!