It depends. The water and beaches are largely the same, of course. But, the Western Caribbean
has far fewer islands and they are farther apart. So you will typically visit fewer islands in the same
duration cruise. Furthermore, Western itineraries can include mainland Mexico stops as well.
In some of those you can get reasonable access to the Mayan ruins and all of the history and
culture associated with them. Finally, if diving or reef snorkeling is important to you, some of the
Western islands have the best diving in the Western hemisphere.
The bottom line, I think, is that the East and West are different, but a wonderful cruise can be had
in either.
Ted