http://www.argos.co.uk/static/Product/partNumber/0813307.htm

This is the 'big' prime I think..

I quote:

The heroic Autobot leader returns tougher than ever to face his biggest challenge yet.
Super sized figure transforms into three different battle modes and includes electronic lights and sounds, to fire up the action.
Use his Planet Key to reveal the ION blaster and snap out hidden twin rocket launchers.
Batteries required 2 x AAA, not included.
For ages 5 years and over.

http://www.argos.co.uk/static/Product/partNumber/0813314.htm

Ultra size are £16.99 too BTW.

And more expensive than the Voyagers which weren't reduced.
Something about this unsettled me on a profound level and I didn't buy.
(Oh, and they had jack squat)