
Coway
Airmega AP-1512HH Mighty
Durable, effective for allergens/odors, but loud on high.
Running these analyses costs money. Buy through my links to help keep lights on! I may get a small commission.
I have four BlueAir units. I bought the first one in 2020, and they haven't stopped working a single day since. I live in Jakarta, and I have plenty of proof to verify their quality. Mine are ProL, ProM, Classic 402, and BluePure. I like to keep them oversized so I can keep them running at the lowest possible speed. I don't have much experience with other brands, but I think BlueAir units with quality certifications are a good buy. I have allergies and asthma.
We have been using Blue Air for over a decade and have been happy with them. Have the 411, the pure fan, and our first one the 400. Had a couple fan issues over the years but customer service has been good so far.
The Classic Blueair models with carbon filters work fabulously, yet I have only seen them priced as low as $300 when on clearance. You can still easily get filters for clearance models, though.
We use BlueAir Classic, they’re quite effective and are WiFi enabled. The companion app is sometimes frustrating to use but it’s outweighed by the fact that they have an API and can be automated. So I have the purifiers run a different speeds based on the values of our IKEA Vindstyrka.
Multi level approach works well. - Decent filter you change more regularly for your HVAC (agree with others that MERV shouldn't be too high) - Clean floors, if you have carpet get a deep carpet cleaning annually - Room air filters. I've had luck with Blue Air. Have one jig one for living room and some small ones for the bedrooms. - Have you tried using regular saline rinses for your nose? I use the powder saline mixes with the plastic applicator from NeilMed, but there are others out there. While my allergies are pretty mild, I haven't needed to take any allergy medicine at all since using these.
The replacement filters cost too much and hold only 4ish months

Coway
Airmega AP-1512HH Mighty
Durable, effective for allergens/odors, but loud on high.

Levoit
Vital 200S-P
Smart, effective dust/odor; some find replacement filters pricey.

Winix
5500-2
Budget king, durable; poor VOC removal, Plasmawave disliked.

Coway
Airmega Mighty
Durable, great for allergies/dust, responsive auto-fan.

Winix
5510 & 5520
Good value, durable, effective for pets; carbon filter issues.

Ranked #1
IKEA - UPPÅTVIND

Ranked #1
CleanAirKits - Corsi-Rosenthal Box

Ranked #1
Austin Air - Healthmate Plus

Ranked #1
Winix - 5500-2

Ranked #1
Coway - Airmega 400

Ranked #1
Coway - Airmega AP-1512HH Mighty