For a sand car i dont agree with a helmet for any of them, most owners do not have a race background so they do not know how to wear them, they drove a dirt bike and think it is the same,
If you wear a helmet, but do not wear a neck brace, then you will most likely cause more damage or break your neck, For the type of speeds and roll over that can happen, a hauns helmet device should be worn,
When i lead, I feel i do not see well out of a full face helmet, I wear sunglasses, I have used a helmet following and it is nice to keep the sand %100 off your head, but does feel clunky.
It seems that safey is not really pushed hard in our sport, a lot of seats really would not hold you well some of these vehicles, and i see so many people that do not know how to buckle up the seat belts, they focus so much on the harness side, that you see the buckle up on there belly button,
A SXS was built to have a helmet on, sand cars have more room from the head to the bars when they are built for a owner, I dont think a SXS was ever built no to wear a helmet.