I think this is the car seat we are going to try and use. I told my husband about this and he said, "A kid who weighs 80 pounds will still be in a harness seat?" I said of course but then I thought will my child start to fight this as he gets older? Also, I'm a FTM so old was your child when they weighed about 80 pounds? Have you found that a child would outgrow the height requirements before they reach the weight? Thanks!!