Child car seats - To isofix or not to isofix?

[Humblebottomous]

I’m wondering whether to get a new car seat for DS, nearly 5. He’s currently in an old, non-isofix, Maxi-Cosi high-backed booster, previously used by another child in the family.

I was under the impression that if the child is secured with a seatbelt then NON-isofix is best as it moves with the child, supporting their back if you have an accident.

So working on that basis, if I buy an isofix one, would a 5 point harness would be best? Surely there’s little point going for isofix if the child flies forward with just the seatbelt to protect them?

But is a 5 year old too old for a harness??

For high backed booster type seats, it's not that Isofix is bad it's more that it's not really necessary. However it's not totally pointless, it adds some stability to the seat, which can slightly improve side impact protection and also helps prevent it sliding around as they climb in and then losing the seatbelt buckle.

Also, without Isofix really you're supposed to secure the booster seat with a seatbelt when it's empty, to prevent it flying around and hitting an adult in a crash. Most people don't do this.

The backrest of the seat will move forward anyway, so it stays with the child whether it's Isofix or not.

Maxi Cosi high backed boosters are good, probably better than a cheap/basic one you'd buy today. On the other hand if your seat has been around a while, through a few different children or is more than 10 years old then it might be worth replacing it due to age of the design and wear and tear. Or if you wanted to replace with a top of the range one, then it's likely to be better than what you have even if your current seat is fine.

If you wanted to look at a harness Isofix seat, then for a 5yo the only real option is Joie Bold. It only gets an average safety rating, so I'd only want to use it if you really need the harness for some reason. For most sensible 5yos, a well rated high backed booster will provide better protection.