Academic experience
Money, Markets & Financial Systems;
State and Economy;
Economics of Strategy;
Public Economics, and,
Doing Business in Africa (my personal favourite).
Personal experience
Gained a knowledge of economics from the perspective of a very different country (especially regarding sub-zero monetary policy). It was also very enjoyable to experience the various distinct regions of Switzerland, the food and making friends with students both local and abroad.
Accommodation
I lived in accommodation provided by UniSG, which, though not on campus and near the main station, was still within 10-20m walking distance from uni due to St Gallen not being too large of a city.
Costs
The accommodation is a bit cheaper than Australia, and a studio apartment is only slightly more than shared accommodation in some cases through the uni (obviously not the case back home). Food, especially meat, is far more expensive. I'd recommend a total of $1500AUD or so per month for the essentials of food and rent. Public transport is efficient, frequent and reliable, but expensive, so I stuck to walking wherever I could to save.
Challenge
The biggest challenge was arranging the visa as further details were given that I was going to be leaving Australia months earlier than a typical exchange would require. I did some research in Singapore, then at ETH Zurich for some time before the main studies began.
Professional Development
Better time management. Speaking of which, thankfully I was already quite timely prior to my exchange, but Swiss people will often regard lateness as extremely rude, far more so then back home; heads up.
Highlight
Top tips
Do everything, especially visa related ASAP! Swiss authorities like to work with paperwork, so leave time to mail it to Sydney (along with your passport) and time to get it back before leaving. No, contrary to some of the advice you'll receive, you don't need to go to Sydney in person, it can be done by mail, just email with the Sydney consulate for details first.