I don't think a link will work, as you have to log in, but the top 4 booster type are:
BRITAX EVOLVA 2/3 (ISOFIX)
Price: £110
Score: 77%
This Best Buy seat from Britax did well in our tests, with a 'Good' overall crash safety rating. It's very similar to the Ultra model, but unusually for a seat in this group, the Evolva 2/3 uses Isofix.
Although the Isofix mounting for the base doesn't actually improve safety, it's more convenient to use than the Ultra version, which isn't held to the car except when the belted child sits in it.
Price: £95
Score: 75%
MAXI-COSI RODI XR
This booster seat with backrest is one of the easiest-to-use seats we've ever tested, scoring top marks for every aspect of handling.
Designed for children from 4 to 12 years (15 to 36 kg), it uses the 3-point adult seat belt to secure both the seat and the child.
BRITAX EVOLVA 2/3 ULTRA
Price: £90
Score: 74%
A highly-rated seat that performed well in our safety tests, this Best Buy from Britax is very similar to the Evolva 2/3 ISOFIT model, except it's not secured to the car with Isofix mounts.
Our experts thought this seat was suitable for children aged 4 to 12. There are good instructions and it's easy to carry.
Concord Lift Evo PT
Price: £95
Score: 72%
The Concord Lift Evo PT ? a Best Buy in 2006 and 2007 ? is comfortable, provides good leg support for the child, and it's easy to move from car to car ? something worth remembering if you're a two-car family.
This seat is a booster with backrest, designed for transporting children from 4 to 12 years (15 to 36 kg). It uses the 3-point adult seat belt to secure both the seat and the child.