Thanks for the replies!
Yes, I do try to stick with reasonably natural stuff, in part because I have a ton of allergies and it's at least easier to identify stuff I might be allergic to if it's botanical.
I am def. open to buying online too.
I am using a ton of protein (IAGal's jello-head)--my hair seems to love it, and I can give it a hard hit once a week without even needing to condition after. Most of my hair is...really, really fine. Like, you can barely see it fine.
RE: the whole porosity thing, I'm basing that on the at-home indicators I've read on the boards here, especially the fact that it wets and dries incredibly quickly. I'm reasonably sure about the porosity, less sure about the elasticity.