I don't know how you're measuring "half as good". But I have a high end Dyson. When I first got my Roomba, I cleaned my office floor with the Dyson as good as I

I don't know how you're measuring "half as good". But I have a high end Dyson. When I first got my Roomba, I cleaned my office floor with the Dyson as good as I could going over it several times. Then I set the Roomba loose on it to see if it pulled up any dirt. When it was finished the bin was completely full. I assume not all of it came from the edges of the carpet where the trim meets and that since it was moving much slower it actually pulled up dirt the Dyson had missed. And don't misunderstand this at all, I absolutely love my Dyson.