Well, it depends on a lot of factors. For example, worst case scenario, the bus goes Movies -> Music -> Sports -> Typhoon -> Marketplace -> Pleasure Island... the PI stop being the one that you'd need for Disney Quest. That particular journey, coupled with a slow driver, slow bus, and every red light in the book could potentially take 25-30 minutes. Most likely your journey will not take this long, but it's always best to be prepared for the worst.