As for the difficulty,
do I gain more depending on the difficulty?
Example:
web-ko1.gonspool.com:3333 (korea) diff 10000
web-ko1.gonspool.com:33331 (korea) diff 1000
web-ko1.gonspool.com:33332 (korea) diff 5000
web-ko1.gonspool.com:33333 (korea) diff 25000
web-ko1.gonspool.com:33334 (korea) diff 50000

diff 50000 gives you more coins?