I wouldn't use it, but it is worth noting that there are other propylene glycol coolants in the world. For example:
http://www.tractorsupply.com/en/stor...tifreeze-1-gal
Engine Ice's website isn't 100% factual. The most glaring falsity on there is that OEM's manufacture ethylene glycol. No OEM in North America manufactures coolant (they purchase it) and none are using glycol-based coolants anymore. They've all switched to OAT based coolants.
Hope that helps.