The MyFun website offers a range of tickets to attractions across Australia.
My experience with the website was that the information was not accurate/up to date, and it was often cheaper to buy tickets directly from the venue or on the venue's website.
You also have to pay a transaction fee through My Fun which you wouldn't if you bought at other places.

I did note that they recently had a 4 for the price of 1 on Gold Coast theme park tickets, although I'm not sure that's the cheapest way to buy them as there are other great deals available on other websites.

I wouldn't go out of my way to buy through them again.