In general, slow flowing teats are better for your baby. If your baby completes bottles comfortably within 20-30 minutes, no change is needed. Consider a faster teat if you notice consistent fussiness during feeding or significantly longer completion times over several feeds. When upgrading, pace the feed initially and hold baby more upright for the first few feeds while they adjust. If baby consistently struggles with the new teat, it's too fast - return to the previous flow rate. Feel free to approach your paediatric feeding speech therapists to find out more!