I have Banco Popular, they charge like 45 for checks of which I have yet to write one, they charge 5 dollars a month if your balance falls below 500 and 4 a month if 500 or above. Since I have yet to use the cards and checks all I seen is 3 dollars a month deduction up to this point. It is very popular bank but many people I talked with say to use a credit union instead which are cheaper, but I do not know for sure as not yet living there and not using a checking account extensively.
I set up Banco Popular because it was the only bank that would let me open a checking account without a PR permanent address. None of the others would let me open the account without some proof of living in the island.
I would suggest to get a BPP account at first to move money from the states and help you get established. After you are in the island and have a permanent address shop around for a better deal.