For a small medium room (carpet) What would you your first and second choice? 1.Blueair 3410 (aud 450 dollars) 2. COWAY AIRMEGA MIGHTY AP-1512HH Air Purifier (aud 323 dollars) 3.COWAY AIRMEGA 250 (aud 380 dollars) 4. Winix Zero+ Pro 5 Stage (aud 365 dollars) I've been doing so much research for days but cannot decide it on my own. Thanks so much :)