In most of VIC past Horsham, it was all 100 k/h, but from Melbourne to Horsham it was mostly 110k/h once you got outside the city limits. In SA, its very much solely 110k/h - very little 100k/h from memory.
Oh, thats another point, I self upgraded the entertainment unit (geez, Hyundai made that super simple) and it added a couple of great features. Apart from the GPS speed, it added the calculations required for the Average Speed Limit cameras - it shows the average speed you're maintaining for the distance between the start and end speed cameras. So easy to stay under, and also not sit there wondering if you're going to cop a ticket.
For the most part, I think I stuck to 115-116k/h indicated in the large part of 110k/h zones, as that translated to 109-112k/h GPS indicated speed (I checked the onboard GPS against my phone GPS, via the IOS app Sp33dy (also via Waze, too). I may have had points where I pushed the limit (mostly after overtakes - I genuinely hate being on the wrong side of the road for too long) for a fair distance. So the economy is actually really good, considering there must have been ~50-70km where I possibly was not travelling at the speed limit.
My insurance policy gives me a free windscreen replacement. Might have to consider that if a repair is still noticeable. Right now, its there and my eyes naturally get distracted by it - cant imagine that'll be safe in the long run.