Order in two sizes from CRC, send back the one you don’t like. Or…. shock horror… send them both back, and order from a cheaper shop online.
They’re a pretty average fit really, a little more wider in the middle than narrower helmets – like the Troy Lee A1 or Fox Flux/Striker.
They fit true to size also, so if you’re on the cusp – think about if you want a tight fit or a looser fit with a bigger looking lid.
There’s also black plastic padding inside the lid, it makes the lid painful to wear – if you find the same, just remove it. I did, and lots of others have too.