Be wary. Jetstar has very stringent rules on baggage - both carryon and checked. Carryon not to exceed 7kg combined, checked based on ticket value (can buy up to 40kg). Their cost per kg overage is not something to mess or chance with. Weigh your baggage and determine if buying up is worthwhile on your fare....that's if the luggage is able to be interlined and get there with such a tight connect