I dont want to start a food fight with some of the folks that have posted things above... but Argentino Spanish will work perfectly in all South and Central American countries.... and it will also work perfectly in Spain. Not to hurt anybodies feelings, but if one learns Argentino Spanish and finds one is getting weird looks its not because of the Argentino, its because your Argentino is not good enough to begin with.

Yes, there are some nouns that are unique, but if you have proper command of a language then anybody with a basic IQ should be able to work around potential unique nouns though context, tone, etc......