There is a most excellent article by Pat Bedard on page 24 of the July Car and Driver. The gist of it is that Pat was questioning what is THE best anti-freeze, especially for use in older cars and/or ones that see a lot of garage time.

ZEREX makes a super extended life product for long-haul trucks, this stuff goes 300,000 miles and then you just add a quart of an additve mixture and go ANOTHER 300,000 miles! The article talks about several other products. It also talks about how anti-freeze actually HURTS the ability of coolant to transfer heat. I mean, I know that straight water is best for this, but I had no idea that ethylene glycol was 25% less effecient than water! But the article also illustrates why you can't use just straight water.....the cooling system INSTANTLY starts to rust, with quick and catastrophic damage to follow.

Anyways, it is a good article, especially since our FDs fall into a variety of the catagories mentioned in the article.