We have been using this glass cleaner for a fair amount of time, and it is now always clean at home. When it is not in use, I take it to either my mother's or sister's house, where they are always happy to see me, and I wash the tiles and windows there. My opinion is that every room in the house should have one of these robots, and this is especially true for any closets or bathrooms that have mirrors on the ceiling or tiles. In general, after weighing the benefits and drawbacks, I can say that this robot is worth its price, especially considering the fact that it is consistently available at a significant price cut.