I did three weeks in Australia two years ago, including a Spirit of Freedom trip. I brought my own gear. I had two buddies along, and they rented everything except mask, fins, and snorkel. Both plans worked.
A lot depends upon what your gear is. If it is pretty much standard kit, then you might be more inclined to rent. If you (like me) prefer a BP/W, long hose regulator, etc., then it will be more worth it to bring your own. We also did a day trip (3-tank dive) out of Port Douglas, and I had to explain my kit to our DM. She had never seen anything like it before, and she was not sure it should be allowed. Throughout the day, other DMs stopped by my station to see my bizarre gear for themselves. None had ever seen or heard of it before.