Tokyo is very crowded, like Hong Kong. Most places where tourists end up being are as busy as CWB, so a stroller can be challenging. I know a lot of my Japanese mum friends use slings in town. Having said that, you probablystill want to bring your stroller in case you go to places which are stroller friendly. E.g. Roppongi Hills is a good place for you to go as they have lots of space (outside), nice restaurant and cafes, cinema, and boutique shops. OK, these are nice things for you, and not really for your baby, but like Hong Kong, Tokyo is where adults can enjoy, but not necessarily kids...