I didn't read all of the replies, so I hope the thread did't derail or something, and that this is still relevant. I have a 3 yr old and a 6 yr old, both boys, and the only place the 6 yr old still uses a stroller is Disney. We still take our citi mini GT double, and I plan to take it probably for at least another year, at which time he will be 7 1/2. He can ride when he wants/needs to, and walk when he wants. But then we don't have to ever carry him, which is nearly impossible anymore for any length of time, and sometimes it's so nice to just put both kids in the stroller and just move. No whining about walking, no lagging behind, etc trust me, he can still whine about other things, but at least not about walking!