Well, if you are learning Spanish, it is important to first determine whether you want to master the dialect from Spain or Latin America. As for vocabulary and grammar, I believe you can do that from anywhere in the world and there is no need to travel to a Spanish-speaking country. Chances are, most speakers do not follow grammar rules in their speech. However, for listening and speaking skills Spanish-speaking countries can help you a lot to overcome the speaking barrier and you will train your ear to fast-paced speech. So, if you want to become fluent both on paper and in person, my best advice would be to study first the grammar and vocabulary basics at home and then travel to advance your skills with native speakers.