A light weight helmet is a must for me due to neck issues. I bought a Yamaha Snoforce Helmet at a snowshow about 12 years ago and have since bought 2 more on ebay. The last one was new in the box. The Snoforce helmets were DOT and Snell approved. The helmets are quite resistant to fogging due to having a lot of airflow. This makes it a cold helmet, but the new balaclavas make a world of difference on cold days. I do have an electric shield that I put on for when I take a long trip or if freezing rain/drizzle is expected. I should also mention that I generally run higher windshields on my sleds. On days above about 10 F, I am able to ride with my shield open with a pair of sunglasses when riding on my Panteras. On my Ski Doo the wind protection isn't quite as good so I keep the shield down most of the time.
The weight of the Snoforce helmet is 1532 grams. The previous helmet that hurt my neck on long rides was a Polaris wedge that weighs 1674 grams. For comparison my wife's new CastleX Dual Sport Helmet is 1655 grams and my son's AFX open face with goggles weighs1955 grams. I have looked at the BVS2 helmets, but the weight would be too much for me.
The weight and the fit are important for me. The Snoforce also fits me better than the old wedge helmet. I would like to have a newer style helmet with the flip down tinted lense, but I think the added weight and the weight being higher up for the tinted shield would be bad for my neck.
Not crazy about using a 15 + year old helmet, but it is the best I have found. I am always looking for something lightweight that fits as well, but have not found anything yet.