The only reason we use filter masks is to keep crud from getting into our mouth, nose, and lungs, so why use anything that can't seal to your face?
Whether welding, spraying paint, or whatever your job is - that has something you sure as hell don't want to breath in, or some environmental airborne particles that you want to avoid breathing in, like pollens, ash from wildfires, molds after floods, drywall dust, or fiberglass from attics, I know that the best you can do is to eliminate the chances and risks of that stuff getting past your face filter.
A coarse filter, a particulate filter, and other stuff like the valve that keeps you cool while reducing moisture inside the mask. This uniquely layered protection reduces over 99.9% of BFE and PFE at 0.1 micron.
Or trust Popular Science Magazine is right when they list this in the 2017 Best New Products Guidehttps://www.popsci.com/best-of-whats-new-list-2017#page-36
And winner of a Retailers Choice Award at the National Hardware Show http://www.nationalhardwareshow.com/en/Press/Press-Overview/Show-News-Releases/Awards-Ceremonies-at-the-National-Hardware-Show/