Many people will tell you that certain places speak “better” Spanish or are easier for foreign students to adapt to. While it is true that accents and local slang can vary greatly from country to country–and even from city to city, that doesn’t necessarily mean that any one type of Spanish is better than another. It all depends on what you want to learn, and how you want to use that knowledge.
For example, if you wanted to learn Spanish in order to do business with South America, you wouldn’t go to Spain to learn, because in Spain you would have to learn some verb forms not used in South American Spanish. Similarly, if you want to travel extensively in Chile, you should learn Chilean Spanish. Your Chilean accent will help you live like a local while in Chile, and outside of Chile it will still be perfectly intelligible to Spanish speakers.
Here is an interesting article on the unique aspects of Chilean Spanish.