In the search for my first purifier I had it whittled down to this Smartmi P1 and the Levoit 300s. Initially, I thought I'd just have to go with the 300s because of the established name, all the rave reviews, and the availability of filters for years to come. But, as is true with the "free market", the established names can charge more and offer less, and the newcomer to the game has to offer the reverse of that, which Smartmi does—more functionality for less. When I found that the P1 offered two functionalities that the 300s didn't: 1) PM2.5 reading on the physical display; 2) PM10 sensor and readings ( this isn't even being offered on the Levoit 400s and 600s)—I decided on the P1. In addition, I read reviews that relayed that the accuracy of the P1 sensors were better than the Levoit's. I say this as objectively as I can, as I have nothing against Levoit and will be looking forward to their future offerings. In addition to the added functionality, I preferred the look and styling of the P1 as well.I was a bit wary of what I've gotten myself into with all the bad reviews of connectivity and app issues. I'm happy to say that with a bit of perseverance I got connected to both the Smartmi and Homekit apps. My only grip is with the historical data section of the Smartmi app, where nothing shows for me. Other than that, everything else works "smart" wise.Lastly, I'll point out what seems to be a never fully realized PM10 functionality of this purifier. I have to note it does have a PM10 reading, by way of the pollen icon, but not as detailed as the PM2.5, breaking it down numerically, as well as graphing it on the historical data page. In my pursuit of this PM10 reading, I found that on the Smartmi app it was originally intended to label the pollen icon with "PM10" (I've included a screen shot from the iOS app store). For some reason Smartmi decided against that, and there is no PM10 labeling anywhere. For the record, I'm not a scientist, so maybe it was determined that a precise PM10 reading was not necessary, or couldn't be registered in that matter. One interesting thing that the app store screen shot (attached) shows is the potential for a low (green) PM2.5 reading and a high (red) PM10 reading simultaneously. It would be a good experiment to bring some pollen next to the unit and see if this distinction of bad PM10 reading and good PM2.5 reading is possible. If it is, then my gut feeling is that a more precise PM10 reading would be desired.As I learn more I'll update my review. The seemingly unfinished dual-sensor aspect and the faulty historical data section of the Smartmi app keep me from giving this 5-stars. But, I am still happy with this device and can recommend it, as compared to anything else in its class (and even above).UPDATE (5/25/22)By coincidence, I was able to confirm that the readings between the PM2.5 and PM10 are indeed independent of each other. Yet, some of the Smartmi promotional material and copy would seem to show that the pollen icon is representative of a combined reading of the two; such as, correlating the green pollen icon with "overall air condition" (screen shot attached). This makes it all the more confusing that my readings yesterday showed a green pollen icon and a red PM2.5 reading of "Heavily Polluted" at 263 (screen shot attached). It would seem there should be no correlation between the two for overall air quality, but that each should be considered independently.For the record, I'm not attempting to dis this product, but just understand it. I like this unit very much and want to make the best use of it.UPDATE (5/27/22)I had some trouble today with the sensors. Out of nowhere, the purifier started acting sporadic, with the PM2.5 reading going from low to high and back, never settling, and always moving. The PM10 reading (the pollen icon) was not problematic during this time, displaying green. I turned off the unit and cleaned the sensors with air, as the manual states. This fixed the PM2.5 reading, giving me a stable and low reading. Shortly after that I was using an older vacuum with a seal problem and dust was blow into the air and across the purifier; the PM2.5 reading went high, and this time the pollen icon turned red. The PM2.5 reading eventually came back down to normal, but the pollen icon never did. It remained red long after the air had cleared; maybe 15 minutes or so. I turned off the unit and again cleaned the sensors with air. This solved the problem—the pollen icon was green again and the unit has been acting normal since.UPDATE (6/27/22)This purifier is running well and I've had no additional sporadic readings since my original occurrence. I can report that I'm a light user of it, I don't have it running 24/7, but only as needed. The filter life so far is on track to last a little over 10 months.