All kinds of lubricants and anti-corrosion additives in coolants. I wouldn't run water. Coolant isn't the problem.
I'd make sure the water pump is good. 'Performance' in the description of a w/p isn't something I look for - often that means they've messed with the vane design.
Take a look at John's article -
http://www.camaros.org/pdf/corv_cooling2.pdf