Which booster if going straight from harness to booster with no training?

One of my neighbors has a little girl about the same age and size as my DS - will be 6 this spring, around 40-42 pounds dressed, about 45' tall. She is at the top slots on her Marathon and Mom needs to get something soon. She wants to be able to put her straight in to a booster due to whatever reasons. But the little girl has had no booster training at all.

She's been looking at the Vivo and the Parkway. She said she likes the Vivo because it looks like it might cocoon her DD (but will it be too deep in the headwings??) and she likes the PW for the SG. I know she doesn't like the Turbo.

Please give me any advice on what she should do. I wonder if it would be better for her to harness longer but I really don't think she'll go for it. So if she's deadset on a booster, what should she do? What is the safest way to go about it?

Thanks.

I would recommend the Parkway for the added safety of the SG. She can also lock the seat belt for a while booster training.

How would she lock the seatbelt? If I recall, her belt locks at the latchplate.

OK with locking latchplates I don't think she can lock the seatbelt, but I'll let a tech chime in to answer that.
With newer vehicles you pull the seatbelt all the way out and then as it retracts back you hear a clicking and thats when you know its locking.

I really REALLY love the Vivo... SNIFF... but with this being a tiny child who needs a highback longer than my long-torso'd baby who outgrew the Marathon before 4yrs old... I'd go with the Parkway SG.

I wouldn't worry about the lack of booster training... she's 6... I'd simply talk to her first... tell her what the seat is, why she's moving to it instead of the Marathon, why it's important she use it, and then put it in, set it up, buckle her up in it, and go over why it's important that she have her seatbelt that way and sit that way the whole trip.

Then, for the first few weeks, I'd just remind her on every trip that she needs to sit up straight and keep her seatbelt on correctly to be safe. And of course, keep the ears pricked up for any "why" questions.

but age 6 is the age I really feel comfortable with almost any child in a booster, even one on the smaller age for size.

Now, as she loves Britax and you think she might like to harness longer and that her daughter would go for it, you could also point out the Britax Frontier... and how long it would last for the money.

All vehicles sold in the U.S. market since approx. the 1996 model year have seatbelts that lock in some way to facilitate carseat installation, but not all seatbelt types lock in the same way, and not all newer/recent/current model year vehicles have seatbelts than can be locked at the shoulder belt retractor. Some vehicles are equipped with seatbelts with locking latchplates that essentially lock the seatbelt at the buckle when the seatbelt is buckled up, while others have seatbelts with locking or switchable retractors that allow you to lock the shoulder belt at the retractor. More details on various seatbelts types and how they lock is in this helpful seatbelt primer at http://www.carseatsite.com/lockingclips.htm It's not possible to lock the shoulder belt at the retractor for booster training (or other purposes) if the seatbelt has a locking latchplate. It's also not unheard of for a car to be equipped with more than one type of seatbelt in different seating positions in the back seat. Some recent Chrysler/Dodge/Jeep models have different seatbelt types depending on the rear seating position, for example.

Some vehicles with switchable retractors specifically state in the owner's manual not to lock the shoulder belt at the retractor for a child riding in a belt positioning booster seat, without going into a more detailed explanation about why not to do so in the owner's manual. Thus it's advisable to double check the owner's manual about that. In cars where the shoulder belt can be locked at the retractor, if there's no restriction about locking the shoulder belt for a child riding in a belt positioning booster seat in the car's owner's manual or in the belt positioning booster's manual, then it can be a way to help "train" the child to remain properly positioned for the entire trip as the child gets accustomed to riding in the booster and remaining properly positioned. But then there's also the notion that if a child needs to have the shoulder belt locked at the retractor to stay properly positioned over time for every trip in the car, then that child ultimately belongs in a 5-point harnessed seat for safety.