"If you got a $150 head,.... buy a $150 helmet".....
I actually have a $10 head....
Really?.... have her try them on...
Different companies helmets have different shapes.
Beyond that,.... I find Shoei's comfortable, but heavy...
Scorpion's and HJC's, are a bargain, and very good....
Main thing, try them on. And then try on others,... and then try them on again...
and if you think she's pretty,.... buy her a full-face....
and I know you do......