~ Why are some seats so much more expensive, if higher cost doesn't mean higher safety?
~ Are some things just gimmicky (like the Britax Advocate's Side Impact Cushion Technology)?
~Do headwings offer side impact protection, or a fixed object that can hurt the child's head if he hits it in a collision? (I know there's no ratings for SIP ratings.)
~Does car seat weight and materials (steel vs. plastic) matter?
I'm also concerned about chemicals (flame retardants) ... Diono, Foonf, Orbit, maybe Britax use the alternatives.
Finally, we need a decent seat to travel with & be able to install in a variety of cars. Is leaving a heavier, more expensive seat at home compromising safety since an accident can happen anywhere?
I think MommyShannon makes some excellent points.
I'd like to add that while we don't have federal standards (or really any standards) regarding side impact protection, please keep in mind a few things. Being in a properly used harnessed seat provides significant "side impact protection" b/c the child is restrained inside the body of the carseat AND the car. Rear facing offers even more significant side impact protection, b/c the child's whole body, including their head, is better contained w/in the shell of the carseat in a crash--the head is less exposed to flying objects and objects that intrude into the car. Obviously, if the carseat is installed in the center of the vehicle, it's further from intruding objects than when installed outboard. Those head wings have not shown to cause more injuries--the seats would not be approved for sale if in testing the headwings proved to be a "fixed object" that could hurt a child. If that were the case, cars would have to have built -n harnesses w/nothing that touches the child on the sides (no plastic carseat). Those sides keep the child's body from moving more, esp their head. I do think headwings are valuable, esp forward facing, b/c the head flies forward in a crash--out of the protective shell of the carseat. Far better to hit an EPS foam lined piece of plastic 2 inches from the child's cheek, than a piece of intruding metal 4 inches or more away...that's just my own example. Many headwings have materials in them that are designed to crush or crumple--to pad the hit into it. Some are just plain plastic w/the seat pad over them, and I think that's okay, too. It still can help prevent their head from going further and stretching their neck, esp in a side impact or a rollover, which are the most dangerous crashes.
I think the more expensive seats have added comfort and convenience features, as well as features the particular company thinks improve safety. And they might--we just don't know. All seats are safe if used properly, but it is possible that some of those added safety features may lessen injuries and risk of death in more severe crashes. I do believe that. If you afford a more expensive seat that has the features you want, by all means, go for it. If you can't, don't feel guilty. All those other seats will protect your child. And obviously, the best protection you can offer your kid beyond that is how you drive--carefully, with full attention on the road, in a well maintained vehicle (brakes, tires, etc, all in good repair).
I don't think steel vs plastic really matters overall. It may be awesome in certain tragic accidents that are incredibly unlikely. I would not be swayed to choose one of these seats b/c of that feature, unless the rest of the seat would work well for us. Keep in mind the few seats on the market w/a steel frame (Radian, Graco Nautilus & Argos, ??) are often heavier than other seats, so for some people that can make moving the seat around much more difficult and make installs a bit tougher. Not worth it if that's the case. Most seats have an all-plastic frame. Note that they've been around like this for years.
Re: flame retardant chemicals. All seats must have some kind of flame retardant, like mattresses. I nursed my kids till they were toddlers and beyond, fed them organic foods, used cloth diapers, etc. And I do believe that flame retardants can be harmful, BUT keep in mind you can wash the cover and it will reduce the amount of chemical outgassing AND your child isn't naked in the carseat absorbing them thru his skin. Even if he was naked, they still don't leach into the skin that easily. If they did, there'd be no point in applying them b/c they'd dissipate too fast. Also keep in mind that those same flame retardants buy your kid time in a crash that involves fire. Even what seems like a "minor" 3rd degree burn can send your kid to a burn unit hundreds of miles from your home for months. Sad reality.
Yes, accidents can and do happen anywhere, in any vehicle. You buy the seat that best fits your kid, your car, your needs, and your budget. And it's okay if budget varies by vehicle and use. If Grandma only will be driving your son once or twice a month and she needs an easy seat to use and she can only afford to spend $60-100, then you go with that. There's plenty of seats available that will meet those requirements. If more $$ is available and you think a more expensive seat actually meets her needs better, than do that. The seat is useable for 6-10 yrs, depending on the seat. It's pennies per day overall. Sometimes, the "cheaper" seat goes in the parents vehicle b/c that's what works best and grandma has the more expensive easier to use by her seat. Do what works for your family. What matters most is that your child is buckled in properly and rearfacing right now. The rest is just gravy.