Madame Tussauds is one of the tourist destination that you can visit in Sydney CBD. It has 70 life-size wax figure of the most well known/popular personalities in the world. If you have a Merlin Annual Pass, you can have unlimited access to 11 attractions in Australia and New Zealand. If you live around the area, I think it's worth the price. I happen to have one (just because I love going to Sydney tower eye and Sydney Aquarium when I feel emo). As for my cousin and niece, we bought a group entry pass which includes Madame Tussauds, Sydney Wildlife, Sydney Aquarium, Sydney Tower eye and Manly Aquarium.
Warning: Picture intensive post. I can't decide which picture to put. I already sorted them out but still ended with a lot.