They've really cracked down here in VIC, I'm pretty sure that wouldn't pass here Misty. ACT must be different.

In VIC:
Choosing a booster seat
There are three kinds of approved booster seats:
*booster seat (18–26 kg)
*combination child restraint/booster seat
*booster cushion (Please note: Booster cushions are not recommended as they provide no protection in a side impact crash. They are also not recommended for use in seating positions next to windows/doors).
from http://baby-car-seat.com.au/?p=109

They are Not recommended, however they ARE legal.

Also:
Children in this age group vary considerably in height and weight. A child may use EITHER a forward-facing child restraint with an inbuilt harness OR an approved booster seat with lap-sash seatbelt. If you are using a seating position with a lap-only seatbelt, you must also use a child safety harness.
Remember that children grow at diff erent rates. Just because they have turned 4 years does not mean they are ready for a booster seat. If your child is still under 18 kg and fitting in the forward-facing child restraint with inbuilt harness, keep using this restraint.
From http://baby-car-seat.com.au/?p=109

And in ACT:
Child age between 4 years and under 7 years: an approved, properly fastened and adjusted, forward facing child restraint with an in-built harness OR a properly positioned approved booster seat and a seatbelt that is properly fastened and adjusted.
from http://baby-car-seat.com.au/?p=8

Frequently asked questions
What can I do if my child is too big for the restraint for their age?
The laws aim to cater for the majority of children, however there is a provision to allow a child who is too heavy or tall for the recommended restraint to use the restraint in the next age category.

If my child is in a booster seat do they also need to be in a child safety harness?
Booster seats do not come with an internal child safety harness, and are designed to be used with a lap/sash seatbelt and therefore do not require a child safety harness. However, if your child is using a seating position fitted with a lap-only belt then they must use a child safety harness.
From http://www.racv.com.au/wps/wcm/conne...ild+restraints


QLD:
Children who have reached four years of age must be secured in an approved booster seat with a H-harness or a booster seat with a secured adult lap/sash seatbelt that is properly fastened and adjusted. The child must be secured in this manner up until they turn seven years of age.
from http://www.tmr.qld.gov.au/Safety/Dri...aint-laws.aspx




These are Nationally agreed child restraint laws, so the new rules will be universal across australia - it is simply the roll out timeframe that is different.

And to quote myself:
they (cushion booster seats) are perfectly fine (legal) so long as you follow the guidelines: it's just that alot of people don't actually read the guidelines.