The guy at the shop finally say that I must have an "arai head" but he didn't carry them so I had to go find a place that carried them.
Arai has three different internal shapes.
The differences used to be defined on their website. You have to know which helmet matches which shape -- after you find out which fits you.
As for Bluetooth: Find a helmet that's comfortable then figure out is there's a similar one that includes Bluetooth. If not, it's easy to add later. I've got Scala-Rider (Q2) but would probably go with Sena if I was buying today.
- If the Qwest fits well, a Vemar Jiano *might*
be a good choice. It's a flip-up. A friend has one and let me try it on and it fit GREAT. But he has the old, discontinued model that he got on closeout from motorcyclegear.com. I don't know what's different about the latest version.