The 1680mm wide model is the Canning. We used to have a 96 model Canning, same as the Sturt but narrower, lighter, no brakes, shorter drawbar and a smaller toolbox. Although ours had a Sturt toolbox fitted. It's targeted at smaller 4wd's.
We looked at getting another, but I'd personally try to find a Sturt, the extra width for storage and kitchen would be handy.
The older ones had a chipboard constructed kitchen, while the newer ones have an ali checker plate one. Other than that and a gas strut assisted tent lift they are largely unchanged.
We looked at geting another one last year (ended up buying a Jayco) and priced the side bedroom from Outback, $1,650 to retro fit one. I'd rather spend that money on an Oztent.
They are a no bullShit, forget the bells and whistles bullet proof camper with a high quality aussie canvas tent.