Well, I have a SWG in Noetheast-for only about 6 weeks now, but love it so far. We chose it mainly because my daughter has very sensitive skin and chlorine does a job on it. So far with the SWG she has no problems and she swims hours almost every day.
Other than adding some CAL and a little stabilizer, my only additives have been muriatic acid(about 7.00 for a gallon-I add about 4-5 cups every 8-9 days) and a couple of cups of baking soda after a big rain to up the ALK.

MY BIL in Houston spends a few hundred dollars a month on chlorine and algae preventatives and a few hundred to treat a pink algae bloom alone-thanks to major pool store chain. They found out later of a fix that would have cost then about 50.00 Gotta love those pool store chains!
It's my understanding that SWG have been around over 20 years in Australia and that more than 80% of pool "down under" use the SWG.
This forum http://pool-information.com/forum.html used to have a number of Australian members. Might be worth your while to check it out.