I started out using those guns and really liked them. THey are great for beginners but after a while of using them the spray pattern on them always seems to mess up. Now that I work at a dealership we use Iwatas and satas. So Far my favorite clear gun is the silver Sata RP with a 1.5 tip. It lays dupont production clear on like glass. I also used Dupont Apperance clear and Spies clear and it also lays it like glass.
The harbor Freight guns I dont think you can beat for the price. I sprayed a small 2 tone kandy with one a long time ago and it came out great. ( The gun was new though)