Pep Boys, Advance, Discount, etc.
It may work to give you lower temperatures but I would be wary of using it. Having used it in the past, I've noticed that a brownish sludge develops after prolonged use. This was both in my own car with a fresh flush and another without. I have also noticed the same buildup when using Water Wetter in water cooling rigs for CPUs. I'm not a fan of it.