I never thought about that press-n-seal stuff. Let us know how it holds up to being in your kit for a while.
I've done something similar for quite some time using mylar food pouches (Seal-a-meal, Tilla). But that's a fair bit of work - seal a row, cut off, slide things around and double seal between doses, cut apart. It's so much work that I've been meaning to order the little packets instead - for those things available that way. (Not as small, but good enough)
Tom