I would know because I've been using the cordless Dyson for almost a year now. I got it as a birthday gift from my grandma, and it's honestly one of my favorite birthday gifts ever. I used to DREAD vacuuming. I hated how long it took, how you had to keep stopping to unplug and replug in the cord, and how mundane the whole experience was. Well, not anymore. I honestly never thought I'd be the kind of person to get excited about getting a vacuum, but this baby is brilliant. I can vacuum my whole apartment in about 5 minutes (it's pretty small) without ever really stopping. Plus, it has different attachments that help me reach those hard-to-reach places (*cough, cough* under my couch) that haven't seen a vacuum in years.
Promising review: "I would have never bought this in a million years, but it was a birthday gift, and I have to say, I absolutely love this. I have waited almost 2 months to give this review to see what it was like, and I have to tell you I am so pleased. The first time I used it I had just vacuumed two days before. I used my new Dyson over they supposedly clean floors, and I filled the canister up. I have mostly Hardwood, and porcelain floors with some carpet and area rugs. It works equally well on all of them. I love it so much that I bought an extra battery charger for it so I can take it to Florida and use it in my condo rental. I am shocked that I have a very clean house, and I always have but each time I use this I'm so surprised at the dirt, hair, and dust it picks up. I would absolutely recommended this to anyone, if you can afford it and that would be the only reason that I never dreamed of buying one as it would have been too expensive for me if it wasn't for my now favorite birthday gift. Oh I have to add no cords and a long run time enough to do my house which is about 3000+ square ft. You have to love that, no cords " —tackless
Get it from Amazon for $278.99.