Alen BreatheSmart FLEX

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Overall

#44 in

Air Purifiers

according to Reddit Icon Reddit

Sentiment score89% positive
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Last updated: May 16, 2026

Reddit Reviews

Reddit Icon1-760-706-7425
19 days ago

You’re also paying for decent aesthetics (which is a requirement for myself and many others).

18 days ago

The ones in the post fit into our mid-century modern home fairly nicely whereas most other purifiers clash. We have a few and the ability to swap faceplates has been surprisingly nice.

19 days ago

> isn’t a total eyesore Thank you. The people on these kinds of forums tend to forget we don’t all stare down at spec comparison spreadsheets all day and, when do we look up, we don’t want to see a big ugly box.

Reddit Iconblounsbury
6 months ago

I went with this one for my daughter’s bedroom - she has severe seasonal and animal allergies. It’s currently $249 instead of $349 to boot. https://alen.com/products/alen-breathesmart-flex-hepa-air-purifier

Reddit IconCaprichoso1
2 months ago

Check U.S. Consumer Reports (subscription required) for the best model recommendations. The highest rated model got an 85. Alen Breathsmart 35i got a 43, Flex not rated. There are many filters with much higher ratings.

Reddit IconConBroMitch2247
11 months ago

+1 for Alen. With that size room, the Flex model is perfect. Then I’d grab the “odor” or “VOC/smoke” filter to deal with odors. Just note that the flex doesn’t come with any apps or ionization like the other commenter. That starts with the 45i and 75i models. Also are great but are way overkill for your room.

11 months ago

It doesn’t exist on the flex model. It’s purely mechanical filtration. Which is what you are looking for.

5 months ago

1) Ask r/airpurifiers 2) Alen is really the only true BIFL brand because they offer a lifetime warranty for as long as you buy genuine Alen filters. Plus the filters last a long time too and they are incredibly quiet. Coway and Winix are good too just not at the level Alen is. **Avoid Dyson, blueair and Levoit. They’re junk.** 3) As for sizing, this part is important: most manufacturers advertise crazy sqft numbers (1,000sqft+ for a tiny tabletop unit) just know that most of the time this is disclaimed by stating it can filter all the air in a 1ksqft room ONE TIME per hour. If you actually want to filter your air, industry standard is FOUR times per hour. So in reality, that 1ksqft unit is really only good for a 250sqft room **on full blast** which is usually loud. What kind of space are you trying to purify? An Alen 45i or 75i is great for living rooms and open spaces, then A flex or 25i bedrooms would work well.

7 months ago

Not a Dyson. Seriously. Alen, Coway or winix.

7 months ago

Dyson in general is not known for high quality especially for the price they charge. Also their customer service is shit. The other 3 I listed are much better options. You’ll want as much carbon in the filter as possible. Alen VOC for example.

Reddit Icondouglass_wildride
11 months ago

Alen is the best. I got this deal. 2 in kitchen/living room and one in bedroom. Amazing for smell and pet allergies. Only downside is filters are $80-$100 but they last for around 6-9 months. I also buy extra filter covers to make them last longer. https://alen.com/products/buy-2-breathesmart-flex-get-the-3rd-free

Reddit Iconhybrid889
10 months ago

I like Alen - they're filters aren't too expensive, they're quiet, and use a lot less electricity than other air purifiers I've seen. I've had this model for about 7 years now and no issues. [https://amzn.to/3H6Nhu8](https://amzn.to/3H6Nhu8)

Reddit IconIDontLikeYourToan
15 days ago

Alen Air all the way. Tried just about every purifier sold From Target, Walmart, Kohls, Home Depot, Best Buy, Lowe’s, Menards… Almost all went back Shark used to be good, but their newer filters smelled like chemicals and they were super loud. Germ Guardian was ok, but quality dropped. Dyson is a joke. If you can still find Alen Breathsmart Flex, that’s the best bang for your buck. Locally, you’re more likely to find the 45i. Get one for every room. Check which filter comes with it. You’ll want the one with some charcoal. Surprisingly, the one with less charcoal worked better for VOCs in my experience than the one with. Put one in each room. Maybe 2 in the basement. You said no budget. Remember, if you “don’t like it”, you can always return it. Check the return policies of the store first before purchasing. They throw away the returns, so don’t worry about someone else getting contaminated with your stuff. Maybe a month from now you change your mind and buy it again, from a different store, just to see. Also, when I’ve dealt with VOCs, air purifiers alone were never enough. Get one of those big orange contractor fans and blow it out the windows or screen door whenever you can. It will also help circulate the air for the air purifiers. A less extreme fan option is the Dreo Pedestal fan, which is a pretty good compromise of price and performance, maybe less loud. Also, look for a good deal on activated charcoal they sell for aquariums. Put it in some cheap cloth sacks, place them in the worst spots, and let the fan blow over them, or in a pinch just spread them on a paper plate if you don’t have animals to knock it over. If my wife sees this post, then by now she’ll know it’s me. Hi Bunny! You can probably pick up a lead test swab too if you’re unsure.

Reddit Iconingodwetryst
8 months ago

I have a Pyr. I got an Alen BreathSmart Flex on sale for my living room and it's made a world of difference. I have 2 Coways for other rooms too. Night and day diference.

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