And another place I've heard ppl posting about is that Tractor Supply has USP-grade PG. I don't have one near me, though.
Ditto on the two years for shelf life. A thread I've read recently by one of the chemists here on ECF is that "two years" is maximum time for shelf life for anything, by law -- even if it's actually good for five years. They have to say that on all products. Don't know what's up with that or if it's true, but just sayin ..........