The Roborock S6 and iRobot Roomba S9 are somewhat evenly-matched, but for different reasons. The Roborock is slightly easier to maintain, incurs marginally lower recurring costs, has a longer overall battery life, and is more effective with clearing large debris, like cereal, on bare floors. It also has a mop attachment to deal with wet messes, but we don’t test that particular feature. Conversely, the iRobot performs better on carpeted surfaces, has a slightly larger dirt compartment, and charges almost twice as fast.