I love my Shark products!  I have used air purifiers since the dr recommended one for my son’s asthma.
The Shark NeverChange Air Purifier MAX is designed for 10x longer filter life.  I’m terrible about filter changes so this is a definite plus.   I love that it gets rid of that musty smell the house usually has after being closed up.  
I love the size too.  It is so much smaller than ones we have used in the past.  
Set up is easy and quick.  I really do like this air purifier.