Which casino you will like depends on several factors. What games do you like to play? If it's poker, there are only two choices: The Excelsior (Holiday Inn) and The Casino (Radisson). Of the two, the Excelsior is the more informal, and has the most games. Do you like glitz (Crystal, Stellaris, Hyatt Regency) or casual (Alhambra, Seaport, Excelsior, Key Largo). Casablanca in the Westin is also fun, and runs somewhere in the middle, along with the Radisson and the Occidental. The only casino I cannot recommend is the Occidental/Allegro. I just didn't really like it. I have never been to the Cool Casino in the Riu, but I have heard it's small.

I would recommend getting both of the nightlife magazines (very small, the size of a large paperback, but not as thick). They have great coupons. Aruba Nights always has matchplay coupons for the Occidental.

I hope this helps. You can PM me with more specific questions. I will help if I can, but I don't know much about the slots there.

Have a great time.