Hi! DS is about to outgrow his snugride, so we are looking for a convertible seat. I have heard the Britax ones are the best quality, is that true? What's the second best? Also, DS is 75%tile so I was thinking of getting the Marathon rather than the Roundabout, but am concerned that it won't fit well in our cars: Toyota Camry and Toyora Matrix. Anyone have experience with these cars?