The Evenflo Reusable bottles are wonderful!  When the babies are under 3 months of age , you have to sterilize the nipples and bottles before the baby drinks from them.  the Evenflo bottles come with disposable liners to put inside the bottles.  All you have to do is sterilize the nipples, put a new sterilized bag into the bottle, and your baby can have her bottle in no time.  When you are traveling or in a rush, all you have to do is take extra bottle liners along with your nipples and formula, and you are on your way to a quick and easy way to feed your child!  I think everyone should try...