As a certified Child Passenger Safety Technician, I help parents and caregivers learn how to properly install and use car seats. As a mom, I take the knowledge I have and apply it to my own family. I can tell you that my favorite car seat, hands down, is the Britax Marathon and its "clones" or "sister seats" (Wizard, Boulevard, Decathlon - same seat shell). It harnesses up to 65 lbs, it has EPS foam lining the shell for added safety, can be tethered while used rear-facing and is super comfortable. Plus, it's very easy to install! Even though the price can be a turn-off at first, if you think about it, it can be less in the long run (add up the infant seat + convertible seat + possibly a combination harnessed/booster seat and it is usually more). For the added safety of keeping a child harnessed past 40lbs, I'll take my Marathon!