Boo boo, we have a meridian and a maxi rider. The maxi rider is great bcos it can be used from about 12kgs I think, maybe less, onwards, all the way until 7 yo or so, when they no longer need a booster seat. It is one of the better ones as you can buy an anti-submarining clip for it (this goes between the legs to stop them sliding them down), one you are using it as a booster instead of a "restraint". Plus it is easy to put in and take out as necessary. The meridian is great too, but you wouldn't get as much use out of it as it can't be used as a booster seat down the track.