JMHO, that looks like it's along the same lines as "Water Wetter" from RedLine.
Although it looks like it plays better with antifreeze than WW. I've used WW and with enough antifreeze in the mix to protect from ice here in the NE, the WW can't help much in that case.
FWIW, I used WW on and off for 5 yrs and really didn't notice a temp difference on the gauge, but I use antifreeze....however I went as low as 25% coolant to water once and did notice a slight difference. This year was a coolant flush year and I did the 45% to 55% coolant to steam distilled water plus one bottle of WW, and I also bought my car a present for it's B-day at BG, a Marc Haibeck standard issue PROM......with the GM standard 180* stat in the car, man what a difference!
Next flush I'm going to leave out the WW just to see if there is a difference in the gauge readings with Marc's PROM. I just have to state the obvious....with Marc's reprogramming of the fan on & off call points my car seems like an ice maker compared to with the OE call points!
