I stayed at the Diria for a conference, but I also had some down time for fun and relaxation. The neighborhood was great, safe, lots of restaurants and things going on all day and evening, but not "crazy" and noisy. Just enough.
The beach was beautiful, and as a photographer, I found no shortage of things to photograph whether it was a walk first thing in the morning, or on the estuary tour booked through the hotel. I also rented a car and was able to venture out to some other places. Just be aware, Costa Rican roads are imperfect to say the least. The main road is OK and leads to several other areas, but the secondary and tertiary roads are often dirt with potholes or moderately paved with potholes. It takes awhile to get used to, but if you're careful and take it slowly, you can get out and explore if you rent a car. Parking is free on the hotel premises.
The conference room was great, and the snacks they gave us each day were awesome. I mostly ate dinners at other venues to try local restaurants, but the gelato place at the hotel was out of this world! I ate more ice cream in a week than I ate all year! And the breakfast buffet at the hotel was extensive. I couldn't decide each morning what to have. Though I did go one morning to the Breakfast Grind, which was fantastic, and I had a little lunch at the Waffle Monkey which is not to be missed!
Hanging out at the pool bar one afternoon with new friends I met who were vacationing there was great too!