I played with Evans coolant for some time. It is interesting stuff.
First, a normal water/antifreeze mix cools better. I got a 15 drop in temps when swapping back from Evans. This is only a real factor in a car where you are at you cooling limits. If your not at your cooling limits it's not a factor.
The limitation of water/antifreeze is it's boiling temp. Ideally you want engine temps warm (not hot). Gas vaporizes better, oil functions better and it helps keep moisture evaporated.
The problem comes in if you run a car with a temperature of around 190-200 (as displayed on your water temp gauge) you ill have spots in your engine hotter then that. Hot spots in the engine can boil away the water leaving a vapor pocket. This grows leaving a larger vapor pocket. Yo may never know this is happening or it may rear it's ugly head after a heated run.
With Evans, the boiling temp is much much higher. You can run 210 degrees all day long with no risk to hot spots. And you can run a zero pressure cooling system.
Draw backs are slightly less overall cooling, replacement coolant (on the road) and flammability. There has been a couple wrecks where the spattered Evans coolant ignited burning the driver.
If you have maintenance on the rod and you need to replace some coolant, your options are very limited. There is a coolant you can buy from autozone to mix in limited amounts (I forget which one). Your only other option is to drain the coolant and replace it entirely because you can't mix it.
This also means if you drain the radiator, Evans is expensive enough that you need to collect it; which is fun.
I still think a lot about having a coolant that is flammable.