WELL i have few guitars with the same J50BC pickup with an Original JE-1000 and it sounds even sharper than the modern EMG pickups, Alexi Played a HELL of a lot tighter back in the day, the jackson guitar was a little higher on his body with a strap that was shorter, he later started to became more American stylish with a lower hanging guitar and that doesnt help on the tight playing, than he broke his arm and he did al weird shit, pretty sure Drugs fucked up things too,. Back in the day it was more Alcohol i quess,. Nowdays Alexi just look very Unhealty and i think it has influance on his playing too,