I tried my first AI last year-Jamaica. I had been on 2 cruises and figured I'd try something different. Here's what I learned:
1. If you are limited to when you can travel, and it happens to fall during hurricane season, cruising is better. At least the ship can move around or re-route. On land, you are stuck there hurricane or not (power went out, no housekeeping, 3 days of pouring rain/winds, bars on resort were mostly closed and the list goes on...)
2. The food was leaps and bounds better on the cruise
3. AI-just a beach, bar...
4. I think one has to be williing to spend boku bucks for a good AI. Like the previous poster said, I tried to go to a cheaper AI in Jamaica (Riu), and could have spent less to be on wonderful cruise.
Cruising is so much more entertaining. AIs-no schedule of activities for the day. Maybe an organized volleyball game or exercise on the beach, and a nightly show.
Carnival Inspiraton, Feb 2006
Carnival Glory, Aug 2007
Carnival Liberty, Aug 2009