I've done more traveling with these shirts - here's an update, and also a new one I haven't tried...
Wool & Prince - great looking, crisp, and apparently really can tolerate multiple wearings before dry cleaning. I've gone about 6 (with a couple of lengthy rest periods in the closet), and people aren't avoiding me yet. At least, more than usual. Still looks almost like new, mild wrinkling at the elbows and tails.
Mizzen & Main - Very nice shirt other than the lack of a chest pocket. Watch out for different materials/weaves. One of mine (fine blue/white pattern) is very stretchy, doesn't wrinkle, washes and dries very quickly. The other (solid white) is a finer weave, slightly less stretchy, and seems to have some persistent fine wrinkles. Not very noticeable, still fine to wear, but unexpected.
Port Authority - I bought a couple more of these, and they are my go-to shirts for long-haul flights. Stretchy, comfortable, and wrinkle resistant. The darker colors like black and dark gray look a little better than the light blue, IMO. Easy to wash in the hotel, dry quickly. Not as formal as a starched cotton dress shirt (or the Wool & Prince), but will get you by in many, if not most, business situations. I'm tempted to round out my collection with a white one. A steal at $24. (Amazon -
)
And, here's a new one I haven't tested yet: a long-sleeve from Arcteryx. (Amazon -
) Looks sharp, very good reviews... Moisture wicking, quick dry, UPF-rated. The flap pocket and odd yoke construction make it more casual looking, though. Perhaps OK for casual business wear.