NOTE: This review is for the eufy RoboVac 30, NOT an 11. For some reason, Revain has combined the 11 and 30 review into one. UPDATE - 09/2018: I have uploaded a video to show that the RoboVac 30 is having trouble moving from bathroom floor (linoleum) to carpet. This started right after 2 months of ownership. PREVIOUS REVIEW: Having owned several Roomba's, I decided to give the Robovac 30 a try. The two most important things I see are: 1). "Ghost Wall" Often the unit will move in a straight line with no obstacles, but will suddenly stop and turn around as if colliding with some kind of "ghost wall". I've tested it in various places (carpet, kitchen floor, etc.) and it still occurs randomly. I've tried cleaning the device with a wet and then a dry paper towel and also a rag, but nothing worked.2). Brush Cleaning Tool Hairs on the brush become tangled over time and are very difficult to remove. This is a common problem with ALL robot vacuums, which is why Roomba includes a brush cleaning tool. If you search "Roomba brush cleaning tool" you'll see what I mean. Now it looks like I'll have to change the brush more often, which is an additional expense.