We have the S&S Unity capsule and DD2 is still in it quite happily. I love it as it takes them for longer (12kg) and also can be clicked in and out of the car with bubs in it, which is sooo handy when they fall asleep. DD2 often falls asleep 5mins from home and I just carry her inside in the capsule. I think they are around $300 to buy new but can be resold for over $200 if they are in good condition. The base is also curved so if they are in it out of the car you can actually rock the capsule.

I think the S&S old style ones are ratest the safest but they don't go to the same weight and they don't click in and out easily. You can hire these from most councils as well so you don't need to buy them. Ours charges about $60 for 6 months. We figured it was cheaper to get the Unity and sell it as we were always planning to keep DD2 rear facing for 12 months and then move her to the maxi rider like we did with DD1.