Hema Navigator.
I got one in December last year. It was ( and still is ) a bit expensive at just over $900 retail, but you now see them on eBay etc a bit cheaper. They come with Route 66 for your standard Australian Street Navigation and Ozi Explorer for you off road needs. Also comes preloaded with Memory Map. Hema maps form part of the package.
The best feature of this unit from my perspective is that you can scan, create or make maps of any area you want, calibrate it via Ozi on the laptop or PC and upload straight to the unit.
The Hema came with a 4Gb memory card, but I have copied the contents of this over to an 8Gb which gives me more than enough space for map and other file storage. I have put the original 4Gb away in a safe place somewhere



as a backup in case the thing dies.
It is all pretty easy to use and allows all functions with tracks, waypoints, routes etc.
I recommend it, but that is my opinion and is 100 % on what I had last time, which was nothing for off road use.
There are several other posts on the site explaining how to buy a cheaper unit and unlock it to enable loading of Ozi etc as well as maintaining the use of the traditional street nav software pre installed.
Good luck with your choice. You may also want to look at the GPS Australia web site, they have a lot of good info available.