We chose the Topeak because I already had a Topeak rack and all of their stuff is interchangeable and slides on and off (I had a bag and DH had a computer case). We wanted a seat that would be easy to change mid-ride (so one of us could ride our son there and the other could ride him home- when we just had one). I was also interested in the "roll bar" aspect of it-- supposedly the higher top acts as a roll bar of sorts (yes, you must put your child in a helmet at all times). I wanted a rear instead of a front seat so that my riding wouldn't be infringed upon, and so that my body would break wind and debris for the baby.
|Here it is, with the now 4-year old when he was 10 months old, getting the straps set right for its maiden voyage.|
With the rear seat, a drawback is that the seat takes up all of your storage. I ended up getting a clip-on front handlebar bag and not carrying anything extra, and wrapping my lock around my seat post. I have also gone shopping and locked my goodies to the back of the baby seat and had them flop along on the way home, but this has been quite rare. It only just recently occurred to me that I should sew a bag for the back that attaches to the baby seat, or panniers that are half as wide and fit under the seat and attach to the rack. The lack of storage is quite annoying. So annoying, in fact, that we are looking into proper cargo bikes.
All in all, we have gotten so much use out of this seat and highly recommend it.