VIOMI Alpha S9 Robot Vacuum-Mop, with Auto Dirt Disposal, 2700Pa Suction, 3L Dustbin Capacity, 250ml Smart Water Tank, 5200mAH Battery, MiHome App (Black, 150 Watts)

Now thats a loaded title, but I think that this bot justifies it. Surely I haven't bought every single robot out there and put them to a scientific test (but I have read innumerable reviews for many/most of them) and finally settled in on this one, the Viomi S9. To get into this feature set (self-disposal) today (2021 July) you have to pay considerably more - nearly twice as much for the Roombas or about the 1.5x as much for the Ecovacs combination. And even then then the Roobas come with some major disadvantages (need 2 devices for vacuuming and cleaning, and AFAIK, they cannot navigate in a dark room). As such the real question here is basically this - does this bot deliver a satisfactory experience on the various features it claims at what appears to be a significant discount to the prices of other options?---------- Pros ----------++ Vacuuming and mopping performance is good ++I used the quiet mode (weakest of 3 suction modes) for vacuuming and found it to have sufficient suction already for typical household dirt like hair, dust, small pieces of paper etc. The sound at this mode is like that of a hairdryer running at low-medium and definitely tolerable. The vacuuming proceeds at roughly 1.3 squared meters per minute.Mopping: I used Level 2 (medium) and Level 3 (maximum water usage) for mopping and both work fine. Mop wont clean older dry stains in one pass, but repeating the mopping over an area definitely removes it after 1-2 attempts. S mode is sufficient to clean in my opinion (though Y-mode supposedly gives better cleaning). While I haven't tested it specifically it appears that one filling of the water tank will last ~1600-2000sq ft or more with Level 2 water usage set (which is definitely enough for the mopping).Auto waste disposal from the robot to the base station also works reliably.++ Navigation is robust ++Once the map has been created the robot is very robust in its navigation. It was able to dock successfully with the base station every single time, even when I left less than the recommended clearance around the docking station. If picked up and displaced by hand its capable of returning back to the base station on its own (after the map has been created for the first time) if you press the return to home button on the robot or in the app.It is not affected by randomly appearing/disappearing objects - like walking humans, bean bags, chairs etc being moved around after forming the map for the first time.The anti-drop feature too has worked perfectly every single time I tested it by letting the mop wander off from a ledge - while I was always ready to catch it should it fall, I never needed to (though it mentally always feels a little worrying to see the robot reach the edge of a ledge about 7 ft from the ground - since a fall would basically mean irreparable destruction. But it has always stopped/backed off safely)++ Battery and recharging ++A full recharge of the battery takes about 2.5-3 hours. The robot will return to its base station automatically if its running out of battery and then once topped up with power, will resume its original planVacuuming seems to consume about 1% battery for every 2 squared meters (which takes about 1.5 minutes for our house) at the quiet suction mode (which is sufficient for our needs). I haven't checked battery with mopping enabled.++ Misc. features ++Scheduled cleaning, multiple maps supported (not sure how many - but at least 2 are supported). Multiple virtual walls and no-go areas work reliably. The robot/app supports point and area cleaning as well as cleaning just the wall-floor edges.---------- Cons ---------->> Robot silliness when power is lost on the base stationAs it stands, with the the latest firmware in place, the robot will leave the base station when there is a loss of power (power-cut) - it seems that the robot does not "remember" that it was already docked when the power was lost, and so starts searching for the dock when it (the dock) looses power. I work around this by turning off the robot when its close to the dock and doesn't need recharging (you cant turn off the robot when docked - appears to be a safety feature).I am told by the customer care that they expect a fix for this issue soon - potentially within a month. Its not a deal breaker, but is a definite annoyance on a device/system this expensive.>> Cleaning reachWhile not a big deal for me personally, I think its something every buyer would like to know - in this model the mop (or the vacuum) is not as "wide" as the body of the robot. This means that when mopping close to the wall, the mop will not be able to reach the 3-5 cm of the floor closest to the wall. This is not a problem during vacuuming because the spinning brush "sweeps" the dirt from the edges to the "mouth" of the vacuum (near the walls the robot always moves such that the wall is on its right side so that the brush on the right can be used to "sweep")Also, if your house has a lot of double edged walls (edges like ¯¯|__ when seen from above) then the cleaning around such edges may not be effective since the brush may not reach the inner edge properly. At the outer edge too, about 2-5 cm strip may not be "swept" as the robot tries to avoid the edge and then find the wall again. Obviously this is a small nit pick for me, but hey, its an expensive robot so you need to know what you are paying for.>> MiscThe disposable mop cloths (looks be a fiber-paper composite) are not useful. They dont touch the floor at all points reliably and thus have poor mopping performance and occasionally leave streaks on the floor. I used two of them and have no plans of using the other 8. The reusable mop (microfiber, 1 pc) on the other hand cleans well.My sister also reported that clearing a map cleared both maps we had saved until then for different floors. We havent checked if this was an issue with the app, or if she mis-clicked some option.--------- Tips ---------1. Get a second mop plate (and one or more additional reusable mop cloths). If you have a dusty house then you may want to change the mop cloth when about half the mopping is done. This process involves taking out the mop plate and removing the mop cloth, running it under water to clean the dust/dirt , reattaching it to the mop plate and sliding it back into the back of the robot under the water tank. Now if you have a second mop plate, then you dont have to remove and re-attach the cloth - you can simply slide in the second mop plate with the new mop reusable cloth attached on it. To me this is a definite quality of life improvement.2. Wet the mop cloth when/after attaching it to the mop plate before sliding it under the robot. This ensures good mopping from the get go, instead of waiting for the water pump to wet the mop which takes a few seconds after starting mopping and will leave the first few meters of mopping insufficiently wet. If you are wetting the mop, you can also add a few drops of cleaning fluid (dont add it into the water tank, since its not rated for it) directly to the cloth if you need it (you may also spray the cleaning fluid on the floor if you need more).3. The Mi Home app used to control this robot needs a bunch of permissions to work well. If you are having trouble connecting to the robot for the very first time, make sure your phone's Bluetooth is on and your Wi-Fi network has internet access.---------------------- Overall verdict ----------------------Despite the couple of flaws I noted above, the Viomi S9 definitely met my expectations even if its expensive. I got it for my mother who is finding it hard to bend over occasionally and this looks to be successful in taking over the sweeping and mopping duties from her in this pandemic. There is definitely a learning curve, particularly for older people in using the app and getting familiar with all the various options, but the robot has been reliable in its functioning and I'm happy with the purchase so far (about a month of use). If it lasts a few years, I'd consider it a good buy for my needs.

I have been using Viomi vacuum and mop robot cleaner for over a month now. I have been having a great experience using it so far, so decided to write a review about it. Here are some of the pros/cons about the product that I have seen over the usage last month.Pros:1. Very good suction power (2200 Pa as mentioned in the description). It cleans almost every hair/dust particles off if run at the highest setting (though I usually run it on normal-medium modes only on a day to day basis). Although you usually need to remove thin carpets/mats as their corners usually get sucked up and causes the machine to get stuck.2. Excellent mobile app (Mi home): The mobile app usually lets you set the vacuum speed, water level for mopping, has multi-map feature for multi storied houses, lets you schedule appointments ahead of time, set a virtual wall, no-mop zone etc, all very essential features that let you customize many things as per your requirements.3. Easy to clean parts: The dust collector, hair brush, mopping equipment are very easy to remove and clean and install back.4. Mapping: It produces a very accurate map of the terrain as it goes about every corner of your house. I think LIDAR is the best technology in this department, which is what this vacuum cleaner uses also.5. Finds its way back to charging port: This one seemed like magic at first :D but it consistently finds its way back to port [The charging-dock should be in a reasonably open space and switched on for the machine to find and attach itself to, after it is done cleaning everywhere]6. Good battery pickup: Charge time is around 3-4 hours while running time is easily 1.5-1.8 hoursCons:1. Noise level: One major drawback I found is that it makes a lot of noise when run on medium/high vacuum power. The noise is still acceptable for normal power level, but this single drawback prevents me to set up an early morning schedule for cleaning.2. Map: While mapping functionality seemed immaculate at first, over the time I find the app overlaying the current map with a slightly different oriented map. The machine remained stuck at one point because of this. This has only happened twice/thrice though, so I don't think it is that major, but still a glitch nonetheless.3. Another issue is that the machine doesn't try to move the curtains, so if you have them in a certain area; it will never go under them unless the curtains are removed/ their ends moved to different area. I knew about it while I was purchasing it and the ends of the curtains I could easily move so it was not a show stopper for me, still thought I would put it here so everyone knows.All in all, I think it is a good purchase for anyone trying to buy a product under this category. It is reasonably priced and offers a lot more that some of the more expensive counterparts like Milagrow/iLife making it as one of the more budget-friendly option for users looking to go for a robot cleaner. I certainly have no regrets buying it.