DS is 2.5 in a Britax Boulevard. He's about 30 lbs, so pretty far from the weight limits. Not sure of height but he's pretty average. His head is >90%tile though, so I have always used that as a reason not to turn him. DH and my mom are pressuring me even more to turn though. I do admit it is a pain to buckle him.
He straightens his legs against the seat back and won't sit down. Even when he's being cooperative, it's difficult to get the hip straps tightened appropriately when his legs are crossed or froggied or his hips flexed. This makes the shoulder straps tight to get on him too.
In retrospect, maybe I should have gotten a Radian or something that has more seat room. He does seem cramped. I don't think buying a new convertible at this point makes sense though. I told them he had to sit rearfacing at least up until the winter was over.
How much further can I really push this without buying a new seat? Has anyone gone past 3 in a Britax seat?