>Anyway I guess there isn't really any way to know until I taste it, but do tourists >frequently get ripped off at those
>little stores beside the road?

It's not just tourists. It's pretty much anyone, including Chinese,
that aren't up to snuff when it comes to knowledge on pu'er; also
including unknowledgeable shop bosses. I've been to some shops that
the bosses had no idea what they actually had.