By the way, student dormitory cost around ~200-300 euros per month. And semester fee costs 300 euros per semester (6months). In total, it makes 3900 euros. So, the train is not the most cost efficient solution, if you are young.
I don't think one or the other is a superior way to spend ones formative years, though doing the train thing might make more sense before going to school, as he may form relationships in school that he won't want to give up for riding a train.