Dad’s short answer: Bagless if you want no ongoing cost and don't mind the dust. Bagged if anyone in the house has allergies or asthma. Emptying a bagless bin releases a cloud of fine dust right where you're standing, every single time.

The case for each

Bagless costs nothing to run. Empty the bin into the trash, rinse it occasionally, done. You can also see what you picked up, which people genuinely like and which tells you when a filter needs attention.

Bagged contains the dust. Pull the bag, seal it, throw it out — and the fine particles that would otherwise go back into your air stay in the bag. Bagged machines also hold more before they need changing, and many maintain suction better as they fill because the bag is doing part of the filtration.

Who should buy which

If anyone in the house has allergies or asthma, buy bagged. This one isn't close. Emptying is the dustiest moment in a vacuum's life, and a bagless bin does it directly into your breathing space.

If nobody has breathing issues and you'd rather not buy a consumable, bagless is fine and it's what most people choose.

One middle path: empty a bagless bin outside, or hold it low inside a trash bag before releasing the flap. Helps a lot, costs nothing.

Whichever you buy, check bag or filter availability for that model before you commit. Same rule as batteries and brush rolls.

Dad’s Take: Allergies in the house means bagged. Everything else is preference and a few dollars a year.