Back in the mid 80's, my unit was sent to assist with the bush fires in central Vic....
I'm not saying what we saw was a panther or a puma, but it was definitely a bloody big cat.
Because I wasn't alone, I had plenty of people to discuss it with, and kick around possible explanations. Further, all but one of us was a soldier, the other was CFA, so we were all trained to spot things out bush (shape, shine, shadow, sound, spacing, movement).
Backlighting makes things look black, and so can soot from fires, so color is arguably indeterminate, but felines move differently from canines (bovines, porcines, equines, etc) and what we all saw was definitely feline by absolute consensus.
Size was the only point of contention. Because range is normally estimated as a function of known height of a seen object (man = 2m, thus if man appears to be x tall, then man is y distant), range estimates varied based on what people thought they were seeing. Even so, the smallest estimate of the animal's size was about the size of a Labrador. Most of us put it's overall length at about 2m.
Keep in mind, we spend a lot of time out bush, and we see a lot of ferral exotics, and even the most skeptical of us acknowledged he'd seen the largest ferral cat he'd ever seen....