Which is the best formula for a six month old? Any suggestions?

There are 3 main types of milk powder: Stage 1: Sometimes labelled simply as “infant milk powder”, this is suitable for babies from birth to 6 months. Stage 2: Also known as “follow on milk powder”, Stage 2 is for babies from 6 months old and up. Stage 3: Contains more nutrients and calories, for toddlers 1 year old and up. That being said I think similac is a good option since it has a variety of milk powders.