Although HOBOT 388 is a top model as an independent glass washer, in my opinion it is not suitable, large ones for sure. My expectations were not met at this point. My regular iRobot Roomba i7+ robot vacuum cleaner requires minimal training, process attention and maintenance. And gives excellent results. Found the following diagram: - treatment of glasses with a Karcher steam generator to remove the main dirt and grease - main wash by a cleaning robot - washing to remove streaks with a cleaning robot double pass (different programs) So there are no divorces. And I have not yet begun to use a detergent, because with it the result is worse. As a result, I put 4/5 because it really saves time and leaves transparent and clean windows. Yes, it takes more time than expected, but much less than if you wash Karcher yourself and wipe it with napkins. The cleaners do the worst. Changed four in a few years.