Are you familiar of
Language School? There are lots of offers in USA, Canada and France. For you? Where would you prefer to take up a language school?
Are we talking about Spanish here (I've checked the website and it seems to be about learning Spanish)

For Spanish I, of course, would rather go to Spain to pick up Castilian. South America has too many regional dialects and ways of pronunciation. I wouldn't go there as if you pick up the local dialect you won't be understood elsewhere. The regional differences in Spanish are greater then between British English and say American or Canadian English (I am not sure about Australian though). Anyway,Castilian seems to be the standard. So for me it would be Spain.