The biggest advantage I see is the reduced pressure on the cooling system. I have always run the lowest pressure cap I could and now with Evan's I can run an extremely low pressure or no pressure system.
Other advantages may be somewhat debatable. Like the "steam pocket" theory around the combustion chamber leading to pre-ignition due to lack of coolant in that critical area, maybe... Something else I like is no boil over at even extreme temperatures and very low to no pressure (having been burned a few times by over heated/pressurized water systems). I also like the anti corrorsion factor, Evans is superior to water in that regard. But mainly, I want to try this stuff, someone has to be the guinea pig around here.
The cooling system temperatures CAN be higher with no ill effects, more heat, generally speaking, is a good thing. Engines run more effeciently at higher temperatures. HOWEVER, there is no gaurentee Evans Coolant will run at a higher temp, it may well stay at the same temps you have now. In which case, I may be tempted to increase the temp rating of my thermostat, which is currently 180 degrees, in order to GET more heat in the system. In a case of "over heating" Evans is FAR SUPERIOR to water because it will not boil over.
As for cost, it's a LOT more expensive than water!!!! But not so much more expensive if your already using some of the more exotic
antifreeze compounds on the market today.