Absolutely. One of the best items I own. Since, as a cleric, I usually bind right outside the dungeon where I am grinding/raiding, I have often found myself stranded, somewhere like City of Mist, or old sebilis. Yank this puppy out of my bag, click it, and poof, I'm in North Freeport. Zone to west, click the book, PoK. From there, anywhere I want to go.
Without it, I'm sitting in EJ, auctioning "buying port from EJ to nexus/PoK" repeatedly in the auction channel, until I get bored and log an alt.
while I understand its a convenience, and would be awful nice to have... is it really THAT long a run from EJ to PoK anyways? I know I have made that run (and longer runs) many times
All in all... is it useful? yes, definitely.. but hardly a necessity in life (dont sacrifice gear or spell upgrades for this)
I believe this item to be used for MARR worshipping clerics only, but as of now, any human cleric can use it to port to North Freeport. Be wary if you buy this item and do not worhship one of the Marr's, for it may be changed in a patch w/ no warning.