That's a really fine looking mask.
I've got several n95 masks kicking around. But am saving them for trips inside stores, and if they make us go back to work, I'm going to want an n95 for when I ride the subway.
But for walking around the neighborhood, which we do a lot, I like the idea of cloth masks. My wife made some masks out of t-shirt material. Two layers, and I found that I can slip a number 4 coffee filter between the layers. We got a new coffee maker last year and have something like 200 of the old number 4 filters from the old coffee maker left over. And I got a stiff wire from my shop to slide in along the top of the mask so I get a really tight fit at my nose.
It's not made nearly as well as your mask, Monster, and takes 30 seconds of so to get the layers lined up correctly and the coffee filter situated in place properly. But it feels like it fits well. When I breath in, the whole filter collapses against my face as I suck air in, so I know very little is leaking in through the sides. and my sunglasses don't fog up at all, so very little is leaking out the edges and around my nose when I breath out.
I found a good website
[maybe this one?] that lists the effectiveness of various household materials at filtering. It was interesting.