I live in Japan. My wife has a regular good bicycle with a basket. I have a son who is 1 year and 8 months (he is 11 kilograms and is currently carried in a baby sling). My parents who live in Australia want me to buy a bicycle with a manufacturer installed child seat. I want to know if they're right that a baby seat installed after manufacture by a bicycle shop (I don't think we'd have the tools to it ourselves nor is it sensible) is not as good as manufacturer installed seat? Of course there are a lot of factors that could affect the installation but roughly speaking is there answer.