In my case I have found long hair binds and locks the Roomba's rotating brushes at the bearing points. This means more frequent hair removal from the brushes than it should require. I still use it weekly, but I find this shortfall irritating when I find the Roomba bound up and dead somewhere in the room where it is supposed to be cleaning. One bearing that binds up less frequently with hair is the bearing on the brush roller and that requires a screwdriver to open and remove the hair.
