There are certain rules about folders on buses and trains. Not sure about Syd, but here in Melb, the bike needs to be covered for bus travel. Syd trains are a bit crowded but a bike that size will be OK in the vestibule I guess.
But my main concern is the bike will disappoint you. It is extremely generic with bottom of the range componentry. The Giant is not much better.
I cut my teeth on a bike like that. But I upgraded it soon after getting it. 9 speed. Ended up touring around Tassie with it.
The gearing range of the bike you have in mind is pretty basic too. 14-28T in the back, with 46T in the front, and small wheels, you'll see the gearing is way too low.
Weight wise, it'll be about 12-14kg. Foldies are rather heavy. But it will easily do the 2x4km, that's for sure. And it will be quite flexy as well. Those frames twist quite a bit under pedalling torque.
Have a look at
Jur's cycling photo albums/photo essays for my journey into foldies.