Got one for the wife and myself. Both of us can fit in small & medium sized helmets, just depends on the brand. If you are not sure which size to go with, I recommend choosing the bigger of the 2 sizes you are debating on, cuz this helmet is small for it's size. So I'm glad I got both of us mediums cuz a small wouldn't have fit either of us. Having said that, my wife loves hers, she says it's comfortable, she can see good, it looks awesome, all good things. I really like mine as well....I just need the cheek padding to break in some more and then I'll be set. The hardest part is getting the helmet on & off, but once it's on it's good. Since the helmet is built narrow instead of round it is harder to get on, but once it's on it feels like a normal round helmet (so it's just the initial opening that is tight). It is decently air tight, but you still get some air in your eyes even with the vents closed. But you can go 100+mph still without feeling like there is too much air making it's way in. I will say that this helmet, due to it's shape I'm sure, cuts through the wind better than any helmet I've worn before. My bike doesn't have a windshield and I don't have a problem with a lot of wind resistance in my face with this helmet like I do with my other helmets, so it is definitely more comfortable/stable at higher speeds, which is awesome. Shout out to Jim@MotorsportFreaks for helping me with my order. He was great to work with and allowed me to customize some stuff that other stores may not have been so willing to do.