Am I right in thinking that the shell of these helmets is the same in medium or large – it’s just the adjustable cradle that varies between sizes?

No, they’re a completely different size. My head is 58cm and just fits in the medium with the cage opened all the way to the shell. The medium also sits high on my head exposing a 3cm gap between the top of my ears and the brim of the helmet. The large fits like a helmet should, but could be described as being mushroomy.

I got a medium Rex for junior last week. same size and fit as Giro, nice lid. I’d be tempted if it weren’t for the straps, which foul my specs (prescription)

OK thanks chaps. I’m keen to avoid the Supermario Toad look but fairly sure the medium will be too small

I wear a medium in giro, bell & sweet protection and kask rex. Nice helmet