I prefer Bissell first and then Hoover. I have dogs. I like how the Bissell makes their brush head. It really does clean deep down and is easy to remove and clean. In fact, that's why it's my #1 pick. All the parks are easty to take off and put back on. I refuse to struggle with a cleaning machine after I've scrubbed carpets.
I have a small Hoover for quick rug cleaning if somebody spills something, etc. The smaller version (which is newer) is easy to take apart and clean and reassemble. I like to have the proper size machine for hte job.