DD used one from 4 months when she could hold her head up to when she was about 2 (and I had to wrestle it out from under her to lend it to a friend!!). She loved it and it was a great way to enable her to sit and watch what I was doing during the day to keep her from whinging.

As it is so portable I also used to use it when we went to the park, to playgroup, on picnics, to the beach, to friends houses etc as a portable feeding chair. It was also good as a second highchair for when guests came over with their babies.

I know other people haven't found them as useful as their babies don't like the chair and some babies with really chubby legs don't fit the leg holes. If you know anyone with one, give it a trial to see if bubs fits, likes it and you think it would be something you would use before buying one.