Ordered this last week because my older kid is almost at the max of her convertible car seat and her younger sister is almost at the max for her infant car seat. Figured it was time to train her in a high back booster and if she passes the test, give her sister the bigger car seat. It's been a week and she's doing pretty well. Late nights are tough because if she falls asleep, she tends to slump where the belt is no longer across her shoulder, but as a kid, I remember this being difficult with only just the seatbelt too, so at least she's got the added seat protection. I would not recommend this for any kids under five, as most kids are not responsible enough to constantly sit up properly at that age. My daughter still needs to be reminded a lot, but I did hear her tell daddy yesterday, "I can't. My head needs to be up against the back rest!" So there's hope. It's easy to install, easy to use, seems to be easy to clean. I'd recommend it.