I don't currently use it in my Dart, but will down the road, and I have in several cars. There is an enormous amount of BS and urban myth surrounding this stuff. The military uses it in all their wheeled vehicles so take that for what it's worth.
Pros: Non-hygroscopic, so it will not absorb water. Will not attack paint, which is nice if you have just resprayed your engine compartment.
Cons: Expensive. Not available everywhere. Non-hygroscopic (water will pool in the lowest part of your system so you should still flush brakes every year on a daily driver.)