I have an older Etrex and its great.
A dedicated GPS can do things a phone can't.I have thousands of way points set in mine and when ever I'm on an adventure to a place that I've been to before I've got all kinds of locations of POIs, hazards, lucky fishing spots, and etc.
We fish the walleye run every spring and have a path plotted through all the boat motor destroying rocks in a river that's pretty shallow.
The nice thing is the mapsets for Garmin have guys making free maps all the time,
this site is the best place I've found to get free maps. I looked and they have a few Australia mapsets.
My buddy borrows it every year when we go to a Military base hunt and has killed a buck at the same way point he set 4 years ago every year. It's my GPS and I don't get borrowing rights to it at that hunt.