I should have mentioned there are 2 coats of paint throughout, and 2 coats of plasti dip on top of the paint for the grips, pump handle and CO2 seal. I've roughly handled the gun about 8 times and so far, the only problem is with the pump handle. On the side where your fingertips press when pumping it, the plasti dip is starting to peel. But all other plasti-dipped areas are in perfect condition.
I think I know what the problem is... the pump handle is the only area I did not spray paint first before using plasti dip. So what I will do is peel it off, spray it down with 2 layers of paint, then do the 2 layers of plasti dip. After, I will test the durability again.
Another thought: Most people do more than 2 coats of plasti dip - usually 4-6 or til desired thickness. Since the stuff can be peeled off with ease and without ruining the undercoat, it's just a matter of testing results.
Thanks for the reply!