Sometimes that hotsauce.com link works for me, sometimes it doesn't. I only posted it because it might be a nice way for some Tomatovillians to mail-order if they want.
The Valentina products do usually come in a plastic bottle, sometimes glass bottles. You can't buy retail from their official site, but you can at least see what I'm talking about at:
http://www.salsavalentina.com/products
The Black Label is the extra hot. Not quite as hot as McIlhenny's Tabasco, but getting there, and not as vinegary tasting. Not as expensive as McI's Tabasco, either, at least not in the stores around here. Much more of an authentic Mexican taste.