We have a 4 year old son who will soon outgrow his carseat in height only. He is only 35 pounds. I am trying to decide between one of the boosters for 30+ pounds with good ratings by Consumer Reports, or a Britax Husky. Are the 5 point harness a real safety advantage over one of the high rated boosters? What I really want, of course, is the Fisher Price car seat/booster combo that was rated excellent by Consumer Reports, but is discontinued and I cannot find anyone with stock left. (Anyone know where I can still order a Fisher Price seat)???