Water Wetter is very useful if you're racing. For a street-driven car, it gains you pretty much nothing--your thermostat keeps you at the proper operating temperature all day long, the only time Water Wetter helps is if you're running on the ragged edge.
Seems like the Box's have a fairly good cooling system. Even on the track my engine temp never got near the red, even in SC on a hot day in June. Around town on hot asphalt I haven't noticed any problems - but then I haven't sat motionless in a traffic jam for an hour yet -