I have share a lot in BK that My BB is using CHu Chu Super cross since born, and he is now 7 months la!!! So far very good. From my BB experience....he drink so fast from 0-5 months, only use 10mins to finish 6oz. Now he has changed to eat infant cereral twice a day and he drink slowly (but will drink so fast in morning time)......I personally think as the super cross is designed according to BB need (i.e. milk come out when he drink)...therefore, if BB is hungry, he will drink faster!!! Un??? I think it's a most nature way!!!
Some tips, you can try to use the "yellow pin" inside the package to widen the "air hole" (the air hole not the super cross)..........and you should see small bubbles when BB drink!!! Hope it helps!!!