Thanks everyone, sounds like the waterborne products are still a bit difficult to apply. I have had good and bad results with it in painting interior cabinets a few years back. After I botched a set of cabinet frames, I did find out is that when applied the paint you should use a blower (hair dryer) to help dry the product after applying each coat to the surface. This will greatly reduce the sags, and runs that will happen if the room temp isn’t high enough.
I have a meeting this afternoon with a PPG rep. to talk through one of their automotive waterborne clearcoat that looks promising. I’ll let you know how that meeting turns out