In my opinion, with a 25,000$ salary here, you can live more comfortably than you can in the US on a 50,000+$ salary. For instance, at 500$/month, you can get a spacious 2br apartment that comes with a nice inner courtyard, tennis courts and a swimming pool. You can go to nice restaurants for under 6$ and take the taxi for ridiculously cheap (less than 5$ for a 15 minutes ride).
And don't worry about getting bored. There are tons of bars, amusement parks, movie theaters, not to mention that most commerces close very late (11pm+). And if you're not into Asian girls, a lot of female foreigners are models from Russia/Eastern Europe that haven't seen westerners in a long time. :)
I heard that this is the case in China nowadays too. Boozing and going out to bars in China is dollar-by-dollar as expensive as the States. Real estate is sky-rocketing.
I looked into moving to China as well, your salary range looks comparable to the numbers I was told. But I'm not sure it 25K is even sustainable in Shenzhen. Perhaps cost of living there is lower than Shanghai, but my guess is that it's not that much lower as it's located in the Pearl River Delta.
Whereas Costa Rica lets you stay for 3 months before you need to cross the border to extend your visitor visa. And apparently obtaining a permanent residency isn't difficult if you can prove income from foreign sources.
Costa Rica sounds like a good destination - I may check that out one day.
"The Culture of Fear: Why Americans Are Afraid of the Wrong Things"
http://www.amazon.com/Culture-Fear-Americans-Afraid-Things/d...