How does the helmet fit from front to back. That's the biggest issue I have. VERY tight from front to back with room on the sides. I'm a bit reluctant because these helmets are ridiculously expensive. But if they fit well, then it will be worth it. I am usually a medium, should I go up, down or stay there? Also, where do you buy? Are there any US distributors? Thanks for all your help! Live like you're dying.