They are all very nice IMO. Though Tamarindo has morphed from a dirt street sleepy surfer town to a rather trendy beachfront with nice villas, condo and sushi bars, there is a reason, and that is because it has the best swimming beach, and also offers surf at the same time, its a great walk end to end, or jog, and there is shopping and events from art galleries to plays/recitals and live music on weekends, if thats up your alley, if not, go chill.
Samara is nice as well but its smaller, and the beach life is a tad one dimensional compared Tamarindo, which is both a expat destination and locals like it to. tamarind overall is still a Tico town in feel, and besides a handful off new small developments, its really grown on as a commercial/retail scene, as most the expats live above town in the hills surrounding the town.
I used go here to surf in 2000-2004 and then started going elsewhere is got popular, then I return after a absence 2 years ago, and actually liked what is now a more fun nightlife and diverse age group too. I can fly down for a long weekend of surf, from Chicago to Liberia arriving 1pm, and be on my board at 230PM, surf 4 days and head to airport at 1PM and be back in Chicago at 8PM. For $350 airfare, a perfect escape.
There is a shuttle to and from the airport and Tamarindo for $13.
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