The main problem with the Pro Series is that the price isn't reflected in the level of quality control. Both Indonesian Jacksons I've bought over the last year had serious quality problems. See the threads I started here on my SL7 and Monarkh. At least the SL7 turned out to be a gem once I rewired it.
I don't know their processes, but ESP seems to be able to get better results out of Indonesia, and I presume the same contract builder is involved. I'm guessing that ESP more closely inspects the instruments at the source and sends back the defective ones.