To my knowledge, all the servers are in Japan, so I would think all the lag would be the same.
I don't know about any EST based linkshells, but mine covers pretty much the whole US, with a few people in Canada. I do know there is at least one person in Florida in my LS.
FFXI-Garuda 2003-2009; Lakshmi 2011-8/20/13 (retired)
FFXIV: ARR - Ghost Bear, Balmung server