Just beware...if their car or cab or bus breaks down on the way back...and you're late, the ship will NOT wait for you. BUT, if you take one of THEIR excursions and something goes wrong, they WILL wait. And in Jamaica, anything can happen mon!
I usually dont mind doing tours that are not with the ship BUT in jamaica I ONLY do the ship tours. I dont feel safe on the island anyway much less without other cruisers.