We recently purchased the Blue Pure 311i+ Max for our office, and we've been extremely pleased with it. The unit was very easy to set up, and we've simply left it in Auto Mode since day one.
It's quiet, effective, and has been a great addition to our workspace. Everyone in the office seems to be enjoying it, and we've noticed the air feels fresher throughout the day. The overall user experience has been excellent.
We're so happy with the performance that I plan to purchase another Blueair unit for our home. Great product, and one I would certainly recommend to others.