Summit paint

I have read about paints over the last several months and have learned alot I have some experience with painting and have learned the hard way I painted my dart before with cheap oil base enamel from the local farmers fleet store and while it looked pretty darn good it didn't last is started getting dull within a year and was completely faded and almost see thru in 5 years . So what iv read is lacquer paint is crap what I learned is enamel without clear is crap and urathane has the best UV protection and will last the longest but is very dangerous to spray without proper PPE. Just curious why is base clear better than single if I'm using a clear? I'm using the correct 2k urathane primer urathane paint with a urathane clear is this a good set up that will give me a decent driver paint job? I'm not building a show car or trailer queen. OEM quality is what I'm looking for. Thanks for your help guys