Bought this set when the casters were literally torn. I used to try to only buy branded iRobot spare parts, but with two friends, a wife and a German shepherd in the house, we destroyed the rollers. All that long hair was constantly being wrapped in curlers and clipped. I chose another brand (this product) as they were significantly cheaper. Well, so far the third party whisk/roller has lasted significantly longer than the iRobot brand. I continue with iRobot for about 2 months compared to about 1 month. And yes, I clean the rumba regularly.