Newborn Twins Schedule

Anyone else have experience with newborn twins? We currently are feeding them on demand which is usually every 2-3 hours and if only one twin wakes to eat, we gently wake the other one. Our Pedi says that this is the best approach for twins.  They are pretty much on the same schedule now. Just curious if other moms have a different approach. Also, how much milk or formula were your twins taking the first week/weeks? TIA! 😃