^ Very good idea, i'm sure a change in pickups can help a lot. However like overdriver said the stock ones "usually" are satisfactory enough for normal use until you have enough to upgrade. I still use the stock ones and have had no problems as of yet. Though I plan on putting some sort of Jimmy Page wiring and a PAF style pickup.
As for the China and Korea thing, I have a Korean made Les Paul atleast that's what it says on the headstock.
Anyways it's great, but honestly just try a bunch of guitars (doesn't matter if it's Chinese or Korean), find the one that really feels nice and plays well and go with that. Location of the factory might have an effect on the quality but you should be the one to decide which guitar is good by finding the best for you.
I heard the new LP standards are better cause they are all mahogany now, my Korean one is Alder/Mahogany still plays great though.