I recommend Melbourne, easier to get on... people are friendlier, less competition for jobs.
Totally agree with GT Pedar, I would stay away from backpacker haunts and other Irish, they have a bad reputation in Sydney, leaving jobs ,wrecking houses..Bondi especially> my advice stay away...its 8 years since Ive been there but my brother and friends are still out there and they say its got worse not better.
I went with my missus at the time as well and saw everything ...to be honest with you you'll have better sessions up the coast in sufers paradise, byron bay.. and up as far as cairns...you''l have better sessions with strangers....why anyone wants to go half way around the world and spend all there time with dipsh!ts you meet every day in Ireland is beyond me.... Swedish birds....top less dancing on tables ...beach parties...fcuking best time of my life...so my advice....get there work hard, be respectful save your money and go up the east coast..... Frazer island...whitsunday islands.. green island...amazing sh!t to see...scuba diving on the barrier reef and wild parties.....if you do it right you'll have memories for a life time