Yes, Pumpkin that is correct, and a H-harness is not as safe as a seatbelt.

the whole thing drives me nuts, because there is so much varying info floating around and it is something that should be clear and simple but it is not.
I am trying to do the safest thing for our family and it is frustrating that there are not more car options available considering the new laws force you to use car seats for all children under 7 and there are many familys with 3 kids under 7 requiring car seats.
When I went shopping for a booster seat for DS1, I went to 5 different shops, looking for options as I knew I would likely put it into the third row. The kmart foam booster has massive wings and the seatbelt will not fit nicely around the seat, It looks ridiculously unsafe. So I took it back. Then I bought the hipod I think, or another one similar and it didnt have the anitsubmarine clip. So I ended up buying the hiliner as this came with the antisubmarine clip and is reviewed very safe.
Aside from the risks of the booster being in the car non tethered in the event of an accident and it flying around wouldnt it be safer to use the plastic better booster with an antisubmarine clip opposed to a foam booster? I am going off saftey first, not the legalities.