Hi Stefew
Can I ask what age were the kids for whom Xtal was too heavy? I am also considering getting one and would occasionally use it with air cadets.
According to the specs Xtal weighs 1210 grams with the head strap, would be a little more with the Steam VR tracking clip on.
My real world flight helmet (Alpha Eagle) weighs 1535 grams. The cadets wear similar helmets when they fly (and pulling up to 4 g).