I spent a little over 2 weeks In CR about 2 years ago. Didn't make it over to the Caribbean side, but liked everywhere I went, and very inexpensive.

One thing to note about Manuel Antonio/Quepos area is that it has the only gay nude beach in Central America. It was a welcome break since I was travelling with relatives... It is the opposite end of the beach from the park entrance. A small cove around the first bend of rocks/cliff...

Lots of costa rican's vaction here as well as european and americans.