I always have soy (lactose intolerant) but I'm actually not a huge fan of it (I'd bring my own lactose free milk to coffee shops if I could!) but their mochas taste magnifique!
And their muffins. Oh my.
For any Sydneysiders, or visitors to Sydney, they're located on Norton St, Leichhardt (aka "Little Italy"). And if you go to Ragamuffin for your soy mocha (or beverage of your choice) make sure you check out Bar Italia and their amazeballs carbonara. Incredibile!