I have a big head, and Troxels tend to fit me best - I don't care as much for the "old style" Troxels, with the more plastic/shiny exterior. . .they really felt like I had a bowl on my head. But now I have a Troxel Sierra and really like it. Lightweight, cool, looks good (I got the tan one - has a suede/leathery look on the exterior).
The most important thing is to just go to a tack store, with staff who understand helmet-fitting, and let them help your husband find what will work best for him.