I am new to this site too. Obviously I am biased towards the Daelim S1. I was like you and test rode a few scooters. Most in the 125cc range and 150cc. Without mentioning names, all the scooters were OK and did what they are designed to do. One felt better in regards to torque all over the rev range, build, features, price and fun. Most of all, I liked it and it fit me perfectly. S1 seat height is a bit lower and my great hob nailed boots can touch the ground flat footed(must!!!) & it took my full face helmet under the mightily padded up cruise cushion lounge they call a seat, lol.
As for the Great Ocean Road, that is simply a must. Scooter would be awesome to do it on. In fact, when you do, give me notice and when I ride to Ben Boyd to fish, I will carry on to Victoria, which is only just down the road. Ha ha, you won't ride into the ocean, just take your time and plod along.
Good helmet, cow leathers/boots & gloves with armour and your set.
Good luck and let us know your decision?