When using Optimum Instant Detailer & Gloss Enhancer Concentrate do you guys mix with regular tap water or distilled water, or does it not matter?
Distilled water! Even though you are misting it on and then buffing it off almost immediately I wouldn't want to leave any mineral deposits behind from tap water.
+29.37 for distilled water. I mix everything with distilled water with the exception of APC type products I use for exterior type cleaning.