I bought the Airpura R414 for my bedroom/office air quality, and I have been very happy with it so far. The build quality feels solid and premium, and I like that it is a simple machine without unnecessary smart features or gimmicks.
The biggest thing I noticed is how well it handles odors. I tested it near my kitchen while cooking, and it did an impressive job reducing cooking smells and smoke. I also feel like the air in my bedroom is fresher, and my morning/post-nasal-drip symptoms seem to be improving since using it regularly.
It is definitely more expensive than many consumer air purifiers, but it feels like a serious air-cleaning machine, especially because of the large carbon filter and strong filtration. I also appreciate the simple maintenance and clean design.