CIBanco is everywhere and usually have a guard posted at the ATM too. If you need pesos stick to exchanging at the banks. While we have not exchanged everywhere, the hotel's and
money exchangers don't always give the correct exchange rate and often charge a fee that is higher than your ATM. The banks will post the exchange rate so you can check it out before you take out cash. Also businesses, even the mom and pop shops, will often accept US dollars and occasionally give a better rate than the bank. They will tell you the exchange rate before you buy.