I purchased two of these NeverChange Max Shark air purifiers from Sam's Club a couple of weeks ago, and so far I'm pretty impressed. I have no way to tell if they actually remove 'bad stuff' from the air as advertised, but I can say that they pick up on 'contaminants' almost immediately. In my 2,600 sq. ft. home I put one in the front living area and one in the back bedroom area. Each area is ~1,300 sq. ft., and are basically separated by a long hallway and door which remains (mostly) closed throughout the day. Performance: With the unit on 'auto' my rather unscientific test to see if it was actually drawing air in from throughout all of the 1,300 sq. ft area was to light a cigarette about 30' away from the unit and then immediately put it out. In about 30 seconds the unit went from running on the lowest speed & an air quality reading of 99%, to going into high speed and a reading around 70%. In about 10 minutes the air quality read >95%. I did this with both units and both responded similarly, so there's no doubt the unit detects contaminants and responds, and I feel that the air actually is being exchanged throughout the whole 1,300 sq. ft. area, and rather quickly. I've seen reviews that say their unit always reads 100%, so they don't know if it's working, but that's never been the case for me. The unit in the living area is never on 100% when we and/or our dogs are in that area, which is most of the day. Both units will instantly drop to a lower air quality reading whenever the dogs walk by it (two very floofy Goldens), we're cooking, or we are doing something near it. At night, after we've gone to bed and all is quiet in the living area, that unit runs on high a few hours and only then will it reach 98-100%. Quiet running: On the two lowest speeds you hardly hear the unit and would easily forget it's there. If it's going to continuously be on high speed for some reason, it's loud enough that I wouldn't want it in the same room where I'm watching TV. I can only compare the noise level to my Lasko tower fan - if it is set on #3 out of 4 speeds, I'd say that's how loud the Shark is when on high speed, if that helps. I put the unit in the living area on lower speeds during the day, then on auto at night. I leave the bedroom area unit on auto most of the time; after we've gone to bed it's quiet enough that we don't even notice it. You can also dim or turn off the display if the light bothers you. Odor neutralizer: The cartridges have a 'clean' scent, but it's hard to say how noticeable the scent is when used in the machine. I definitely smell it when the unit first kicks on, but after that I don't know if I'm used to the scent or if it's barely there. As far as the air in the house smelling fresher overall, it's obviously fresher in the bedroom area; I can't really say one way or the other for the living area. I have two dogs that are in the general vicinity of the unit most of the day, and they haven't had any adverse reaction to the scent cartridges that I can tell; since these are more like a 'solid' air freshener-type cartridge that air passes over, as opposed to something like a liquid in a diffuser, I'm assuming these are safe to use with pets in the home. I couldn't find any information from Shark on that, and I think they should make that information available. Filter life: I haven't had them long enough to speak to filter life. The filters and scent cartridges are rather pricey, so I hope they last as advertised. Remote: the remote works fine from several feet away, although I rarely use it. You do have to aim it at the front of the unit for it to work. Automation: These particular units do not have WiFi or any way to operate them other than by using the remote or manually. For me, it doesn't matter, but it would be nice to be able to use them with an app to at least schedule the on/off times. They do have a manual timer with a range of 12 hours, in 1-hour increments. The unit will run for however many hours you set it for, on whatever speed setting it's on when you set the timer. So, if you have the fan set to low, and on a timer of 6 hours, it will run on low for 6 hours; if you increase the fan speed an hour later, it'll run for the remaining 5 hours on that speed. If it's on auto, it will change speeds as needed throughout the time it's set for. The unit has a pretty small footprint and is lightweight, but Shark failed by only making one 'indentation' for a handle, so it's awkward to pick up. Also, the base of the unit comes off with just a quarter turn (to replace the HEPA filter), and if you scoot the unit around on the floor the base can come undone easily because it doesn't firmly lock into place. I put two pieces of tape on either side, which solved the problem so far, although I don't move the unit around now that I have it situated where I want it. Those are two features that Shark should have seen as an obvious, albeit minor, issue that should be remedied in future models. So overall, I definitely recommend these units. I definitely would prefer to have an app to remotely control the units, but as far as air exchange/performance and noise level, I'm very satisfied.

The one we got worked for 5 days the showed an E 1 error code. We called shark and they sent us a new unit. This one seem to not have errors and is not shutting off every couple hours like the original one did. Now that I have a working unit it seems good. 3 stars because the purchased unit was defective.

Had this for less than 3 months and it stopped working. Tried contacting Shark customer service to see if they could trouble shoot anything prior to contacting the store. They refused to help. This is my first Shark product. Returning product back to the store.

Sadly I can smell my neighbors cigarette smoke in my apartment so I bought this purifier. This piece of junk is NOT doing ANYTHING to get rid of the smell. I am returning this piece to crap and buying an IQAir. Just like everything you get what you pay for. First and last Shark I will ever purchase.

I have used this air cleaner for 6 months and am extremely satisfied with the performance. It is easy to set up, easy to use and easy to maintain. I bought a hand held air gun for cleaning electronics and it works great to clean the removable screens. I noticed a difference soon after installing it. I am considering a second one for the second floor.

[This review was collected as part of a promotion.] My living room is open concept and usually I need multiple air purifiers for this room. This one can handle the job. You'd be surprised how at how much normal cooking with a gas stove can impact indoor air quality. This unit gives you a lot of information about what type of air pollution you are experiencing as well as the air quality. I like to use on “auto” mode so it's set and forget. It has been set up for months now and still works great. Haven't had to do anything!

[This review was collected as part of a promotion.] So far I'm loving this air filter. what I love most is you don't have to change the filter. there are 2 sections on each side that you slide up and remove so you can rinse the dust off . It's really not that loud on the first 2 settings but on 4 you can hear it. I mean its not so loud that it would disturb you. It was easy to assemble you do have to take the bottom off and take the plastic off the filter before you turn it on.. it has a little odor neutralizer thats smells really nice and clean it has settings to allow you to choose your level of fragrance. The top part shows you the power button the timer and you can adjust the light on the front and the top in case you like it dark the timer goes up to 12 hours . there is a led light on the front that shows how clean the air is .and it tell s you how clean the side filters is . Having pets can sometimes be challenging as far as allergies. What I love most is you don't have to change the filter and it saves you money in the long run. I will say after a few days I felt like my sinuses were dry so I only run it while cleaning house and if we're expecting company . This is definitely worth every penny I highly recommend it

Purchased this about 2 months ago and have only been able to use it for a few weeks. The big filter on the inside smells horrible! I have a fairly clean house it just gets dusty from a dirt road. I live in the desert so humidity is non existent. The filter smells like dirty feet, it is so disgusting. I've tried cleaning it and it still smells. DO NOT BUY THIS MACHINE.

Love it so much that I ordered another. It's super quiet and I feel like it genuinely cleans the air. I like seeing the air quality reading on it at 100%. I know it works because we have ours set up near the kitchen and anytime we cook we notice the air quality reading drop some but soon after it gets right back up to 100%

My husband has allergies and asthma. Immediately after purchasing this air purifier, his breathing improved. He went from nightly asthma attacks to none. As other reviewers have mentioned, the quality sensor appears to be effective as well. Even without allergies, the air is noticeably purer in our house. We have a large, ~1700 square foot downstairs and this purifier handles it well. The device is mostly quiet and unobtrusive. Although it is large, it doesn't get in our way, and I don't feel like it creates noise pollution. Given its effectiveness, range, and cost, I am very happy with the purchase.