I have owned three of these, this or earlier models, over the last 10 years. They work very well indeed - I live in dusty dirty Arizona, and the difference it makes to my bedroom is huge. Without it, my allergies are much, much worse.
It’s also fun to fart near it - the dirty air sensor really does work, and the machine revs right up to max to clean up the stink
Thanks to my nephews, I can vouch for this statement. Rather funny.
I have a 5300 which I really like. Thinking of buying two of these 6300s for my living room/dining/kitchen open area. These run over $300 for a new one. Hoping the reconditioned ones are just as good and I can put one on each end of the space.