We moved to Oz 9 months ago to an inland city called Toowoomba in Queensland near Brisbane (never heard of it but I got an amazing job there). It is different, sleepy and a little like being in the UK in the 60's where shops close at 12 on a Saturday. However I kinda like it, we get time to walk through the park (instead of shopping), drive down to the beach (even if it is 3hrs away) as the weather is pretty good most of the time and we are less stressed and out of the rat race (although if you moved to Sydney etc I am sure the rat race would be very much the same). We came here with the theory, if we don't like it, we go home but we didn't want to wake up when we were 50 and wonder 'what if'. I do get very homesick sometimes though and that is something that you will have to deal with, I have travelled a lot but never been homesick before (not pleasant) but we have an amazing supportive family back in the UK.
Everyone is different though and we may stay, we may not, who knows but I would never regret giving it a go, no matter how hard it was and how much it cost, as life is short and the world has shrunk with cheaper flights and Skype.
Good luck and at the end of the day, do what is right for you :-)