We bank at Banco Popular. It was the first bank, and for a long time the only bank, to accept accounts from non-residents, although other banks have started to follow suit. I feel very loyal towards them. However, service and attitude vary from location to location. For example, everyone at the branch office in Santo Domingo is fantastic, while in Tres Cantos they are cold and not really good (except for two people). Check around and bank someplace you feel comfortable.