The orange stuff is MAYBE DexCool. I'd say don't use that, it's been known to attack certain types of plastic that are used in cooling systems. It's OK if you change it every 2 years, but then you aren't taking advantage of it's advertized long life.

Check this out from a Saab board.
http://www.saabnet.com/tsn/bb/genera...html?bID=83227
More than you ever wanted to know...