Andy, regarding the optimum car wax. Do you use it as a drying aid? Or do you use it once the car is already dry? It can be used both ways, and I find that when I use it as a drying aid, it not only makes it a LOT easier and faster to dry the car, but also finishes better. You could be getting streaking from either a) humidity or b) applying to a warm/hot panel. I've never had issues with it, but I normally don't apply any type of wax or sealant when it's really humid out.