Have him go to a store and try them on.
The biggest key to not hating the helmet is having it actually FIT. No way to know that without your DH actually plopping it on his head.
I rode in an International for a bazillion years. When it came time to replace it, they had changed their styling just a touch and I was in between sizes and couldn't make the ****ed thing fit well to save my life. I still have it in the hopes its going to magically fit again--I loved my first one that much. But unless its winter and I am wearing a thin cap over my hair and under the helmet, it wiggles all over the place.
I then went with a Tipperary Sportage, but agree with whoever said the newer model doesn't fit exactly like the older model (luckily for me the newer model is a better fit). But moral of the story is, put the thing on his head and let him feel it.