I like Troxel. Your helmet choice should be strongly influenced by what sort of riding you do. I have one for everyday, and one for showing. I suggest you discuss this with your trainer (if you have one), and go somewhere that has a wide selection so you can try different brands and styles. Hair is also an issue – if yours is long you might need two. One to wear with your hair up, and one to wear with it down, as the fit might be different.
It is never the horse's fault