I was in Puntarenas for about 9 months, from August 2013- May 2014. I loved the staff in the University and they offered some AMAZING tour options including a 7 day tour of Cuba which was a once in a lifetime opportunity that I will always cherish.
The host families were very hit or miss, they need to be held accountable more for the roles in the students lives, especially the role in feeding the students- some families let the students eat leftover meals while they went out to eat- or feeding them the basic beans and rice while the host family ate other dishes, make sure they are feeding you what they are paid to feed you.
The community has put a lot of money into the area recently- so the pool at the point has been finished and looks nice- the beach is a nice way to tan and cool off on hot days, although the water is not cleanest, still refreshing. The location was good because the ferry to the Nicoya peninsula is right in town and there are busses to take you all over to prime destinations.
If you are looking for a relaxed time abroad- this is the best location in USAC for Costa Rica- the others are more fast paced and demanding. The professors in the location are awesome- great for learning Spanish. There is a Burger King and Pizza Hut in Puntarenas which was sad, this country is so Americanized, they have Wendys, Mc D's, Popeyes, Taco Bell, Subway, KFC, and other American food chains....
I wish there were more diversity in students, I studied with primarily American students, and some whom, as expected, went to Costa Rica expecting to be in Miami or Palm Beach Florida.... Please remember that Costa Rica is in Central America- a LATIN Country, not North America. The only hot water you will get is in a hotel or the city. Hearing the students complaining got to be a drag- making local friends can help you beat this annoying spell.