I own several other air purifiers, each from a different brand, and here are the ways I think the Levoit stands out: 1. You can turn all indicator lights off with a touch of a button! Why, WHY is this such a rare feature among electronics these days? 2. The night mode, which turns the fan down to a speed that's nearly silent. 3. (My favorite) The buttons don't make any noise when you press them; no obnoxious, unnecessary *BEEP*. 4. No silly wifi "feature."
Now, as to some of the claims by Levoit, this purifier is neither as quiet, nor as effective at odor reduction as they'd have you believe. But that seems to be par for the course for air purifier manufacturers.
Night mode is nearly silent, this is true, but even the lowest standard setting it makes a bit more noise than I expected. With my other purifiers the lowest setting is nearly inaudible. This isn't a big deal to me, but just fyi. And just like every other purifier I've ever owned, the highest setting roars like a jet engine at takeoff, though placement can help mitigate its disruptiveness.
As for odor reduction, this is where manufacturers seem to take the most liberties in their marketing material. I mean, let's be real, it's just a filter. All it does is trap airborne particulates at or above a certain size. Obviously any odor-causing particulates caught by the filter will be eliminated from the air, thus reducing odor. In my experience, however, it seems most odor-causing particulates are either much smaller than ~0.3 microns, or the cause of the odor is in a gaseous state. So don't think this, or any other purifier, is a magic box of springtime freshness. That said, carbon filters do help with odor reduction beyond what a standard filter is capable of. If you've got a fog of funk that isn't reduced by a standard filter, a carbon filter might help (emphasis on "might," as, again, these things aren't magic).
All-in-all I'm impressed so far with this little purifier.