As many of the reviewers have commented, Shakahari is more expensive than most of Melbourne's vegetarian establishments. It also offers a more gourmet menu and atmospheric environment. I treat it as a place to go to celebrate a special occasion, but at the same time, it's in a similar price bracket to a lot of places I used to eat out at before I went veg, and I wouldn't call it expensive. As for the serving sizes, they're perfect for me, in fact, they could probably be smaller. An entree shared between 2, a main, and a dessert, and I'm absolutely stuffed. Usually, I skip the entree to ensure that I have room for dessert.
I love the food at Shakahri, and excluding take-away places, I would have had more meals there than at any other restaurant in Melbourne - and it's nowhere near convenient to where I live. It's also somewhere I feel comfortable taking omnis for dinner, they all seem to enjoy it.
Weather permitting, I recommend sitting outside as the courtyard has a lovely atmosphere, and inside can get a bit noisy.
The tofu caramel is particularly amazing, it tastes just like a really good panna cotta.
Cons: Can get noisy