We used it from Allentown and were very satisfied with it. The bus picked us up at the economy parking lot at the airport and dropped us off at the ship. We paid $2 apiece for the baggage handlers and our luggage was taken care of. We just had to go sign-in. When we returned, we were among the first passengers to leave and the buses were waiting for us in the terminal building. We felt it was much easier than taking the regular bus to the city and then getting a cab from Port Authority or Penn Station. At $50 a person, it wasn't all that much more expensive either.
We took the bus from Providence to NYC just a year ago and found going down extremely efficient.. The NCL rep comes on board and informs you about the luggage handlers (it's a bargain at $2.00 apiece)..went into the terminal, signed in and boarded. On the way home our luggage once we picked it out was taken directly to our bus...no fuss..no muss. They even carried for me a large bulky "take off" from the art auction and made sure it was in the baggage safely on the bus. In my opinion Boston and NYC have spoiled me for cruising and I just hate going through the Miami port with their rude porters and rude is being kind.