You can’t really master a language when you only need to speak it a few hours a week, which is why I applied to study in China for a semester. I’d definitely encourage anyone wanting to learn the language to go on exchange, because you’ll get an immersion in Chinese culture that is simply not possible in Sydney.
And don’t forget to apply for Chinese department scholarships. I was lucky enough to be awarded one of these scholarships, which will go towards my China exchange. The cost of an exchange semester can seem daunting, but there’s a lot of financial assistance available from different sources (the university, faculties, the government, etc.), and with the very generous support and encouragement of the Chinese department, the exchange goal feels much closer.