Diono Radian V - the only car seat you'll ever need?

• Group 0+ - birth to around 12 mths
• Group 1 - 9 mths to 4 years
• Group 2/3 - 4 years to 12 years

This means you face having to buy at least 2, and often 3, separate seats as your child grows, and if you have more than 1 child, the seats keep coming.

As your children legally have to travel in a car in a protective car seat until they 12 or reach the height of 1.35m (just over 4 ft 5), you can easily find yourself facing a bill of £400 and more.

Diono has vowed to change this, pioneering the first all-group car seat.

Plus, the Radian V has been designed to keep your child rear facing for longer. This is something we're seeing more and more of - for example the Maxi-Cosi 2-way Family Pearl and the Britax Dualfix.

• See our 10 of the best rear-facing for longer car seats

This change in design comes following the introduction of iSize guidelines and after clear evidence that children are safer when they sit rear-facing rather than facing forwards.

The Radian V offers the ability to keep your child rear-facing up to the age of 5 years or when they weigh 25kg (which ever comes first). They'll also be able to use the 5-point safety harness until that age as well.

Of course, not all children (or parents) will want to keep their children facing the back of the car for this long - you can imagine the shouts of indignation from 3 year olds! But it offers the choice to parents, and the rear-facing for longer argument is certainly getting stronger and louder in the UK.

So when will the Radian V be on sale?

We're told early next year, so watch this space. MFM was given a sneak preview of the Radian V by Diono at this year’s Kind & Jugend baby and toddler trade fair. We'll be reviewing it as soon as a sample comes into the UK and will let you know what our mum and child testers think...