Pet owners, this might be mainly for you. Vacuum cleaners come either with bags or without. It is proven that the machines with bags are better for allergy prevention and containing pet hair and dander. Cleaners that are bagless have containers that fill up quickly. They have filters in them, but those filters get clogged and need to be cleaned/replaced. The more hair you have to pick up, the harder it will be on your filters. Also, make sure (if you're a pet owner) to buy a machine that sports a brush roller. You can read more about the top vacuum cleaners to get a clearer vision of which vacuum best suits you.