I was watching an episode of wheeler dealers and Ed China went into detail about the benefits of waterless coolant. I had never heard of it until now.
Supposedly it lasts the life of the car, and does not expand like water so you can pop the radiator cap off with the engine running at full temperature. No corrosion, no environmental issues, higher boiling points, and better MPG.
So, its expensive, but you only use it once and its much better for the car. Why isn't everybody running this?
Jay Leno did a video about it last year. Apparently its very popular with diesel truckers because it improves their economy, more heat resistant, and lasts forever.
Jay Leno's Garage: Waterless Engine Coolant - YouTube
I would think just for safety sake given how poisonous regular coolant is this should be standard equipment, EPA mandated. So many other silly EPA mandates while this one makes sense.