Thanks ludmilak!!! I also think gentle's version is alright, "Su amigo de siempre", now that I see it.
Vicente and Alfredo, I guess it's one of those examples of flavor nuances! Trust me that I'm with you about the "misuse" of the preposition "de" instead of "para", but it always sounds like a more "tropical" sound to me... and I like it. (It makes me dream of Cartagena or a similar place where you feel like at a little piece of heaven on earth! .)