Speaking on N/KN95...
I am not any kind of qualified expert. I've been dabbling in masks for 3 months. I was a Chemist long ago, FWIW.
This is my OPINION. Not medical advice.
I've tried to fit more than a dozen KN95 and N95 masks to my face over the past 3 months. I've sent them to customers who know what they're doing, and we've compared some results. The reality is that your face shape, the mask dimensions, your attention to fitting.... all matter.
Most masks you find available these days are flat-fold. Well, my nose certainly won't seal under a metal nose-bridge triangle. You need to spend some time matching the shape of the un-folded mask to the shape of your nose. I've found that most masks CAN be shaped to fit me correctly, but some are better than others.
Size matters. The Honeywell H930 is a great mask.... for my wife and kids. Not for me. Too small.
The H910 however, is slightly bigger and fits me awesomely. And it has a foam pad that seals under my eyes. And it's an ear loop. Bonus.
One of my customers swears by the H930. I assume their staff are all microsyphalic, like my family.
Bottom line... you can make most masks fit reasonably well, but not every mask fits every face.
For running errands and such, I find I'm using 1 mask every 3-4 weeks. The package says 8 hours. I figure 5-6 hours over 3 weeks is ok. Just my opinion.
Put on, buy groceries, hang on hook for 24 hours. Sanitize hands before and after donning and doffing.
There are some great looking fabric masks .... There's a thread going on it here. I gave my kid a fabric mask with a charcoal filter. Supplosed to be >95% filtration. He handles it WAY better than an N95 with ear loops. The velcro is way better for him than elastic ear loops.
The better the filtration, the less likely it will be for you to get infected by others.
You have to strike whatever balance is best for you between effectiveness, comfort, availability, etc.
IMO... I'm not going into any enclosed spaces without a mask that protects my airway. N
Outside in the breeze... depends on the exposure time. Exercising... No mask, distance.
Social distance cocktails in the yard... maybe no mask at all, if I am sitting upwind.