Disagree completely with the quip about helmet peak/visor
ANY peak when mountain biking is preferable no matter how small.Once you have done a ride in a pisspot style / no peak helmet in heavy rain with a headwind you'll realise how peaks/visors definitely fall into the functional category. And helps to keep goggles clear.
Also pretty useful for head-butt clearing low branches on wooded trails. Without getting a face-full or scratching your glasses/goggles.