I am extremely extremely grateful to you for writing this up! I am thinking seriously about switching to elastomerics for travelling, making the same argument as you, that if I can find something comfortable to wear for extended time, I don't need to worry much about communication. But I've really found it difficult to work out what the trade-offs are and seeing detailed reviews of lots of different types (many of which I didn't even know about before this post) may help to unblock me. You've also suggested a possible process I could follow for finding the right mask.

Right now I'm using disposables (3M Aura works well for me) for situations like work or synagogue services where I need to be able to talk to others occasionally, and removing my mask altogether for situations where people are there specifically to listen to me like when I'm leading the service, preaching or teaching. I am fascinated to hear that you can manage communication-intensive activities while wearing a Stealth mask. That, and the fact that aesthetically they're somewhat professional looking rather than medical or industrial might be a good reason to try that. I'm really not happy about teaching unmasked, but didn't really feel I had a better option, and this post suggests that possibly I might.

You make a very clear point about source control; I've been worrying about masks intended for industrial use with outlet valves as I really, really don't want to infect anyone else with Covid if I mess up my precautions. It does make sense that if people are willing to take trains with unmasked people, me wearing a less than perfect mask isn't adding to their risk much.