Saddle Fitting for Aussie Saddles

I apologize if this has been asked and answered before but I can’t locate it. I will be buying an Aussie saddle for riding on the trails. I’ve always ridden in a dressage saddle so I assumed that I’d need a saddle fitter for the Aussie saddle also. But when I ask around, I’m told that other than selecting medium or wide, it should fit my horse. Is that correct?
Also, any comments on ones your really liked or didn’t like?

Aussie saddles are remarkably forgiving with regard to fit. As long as the tree is the right width, you should be good to go. The stuffed panels tend to shape to your horse’s back with use.