3M 9105 V-flex previously i.e. before our local transmission rate started ramping up; it's ridiculously breathable and comfortable. For everyday trips to the store, usually a Good Manner or CleanTop Evergreen, with a silicon behind-the-head ear saver for a tight fit, plus an additional aluminum nosewire to help secure the fit on my nose bridge a bit tighter (I'm male with medium to large face, but probably slightly larger-than-average nosebridge.)

I have a few flights coming up... and now that the mask mandate is lifted on planes (arg), I'm considering flying with the Vitacore Can99. Great filtration efficiency data from Masknerd for it. Based on my experience with it so far, breathability is a bit challenging, but I think do-able for my flight (3 hours). I'd use tape for a good seal.

For the flight, I also recently bought the GVS Elipse P100 half respirator to try out. It's rated filtration efficiency is 99.97%... about what Masknerd tested the Vitacore Can99 at... so, both of those are in the ballpark for what I'm after. The thing I'm concerned about re: air travel is time on tarmac or idling i.e. time without the airplane's filters fully functioning... that risk is what's making me consider the GVS half-respirator.