I may be wrong, but I think helmet (without Hans device) AND seatbelt are a lethal combination. I remember reading about it regarding that motorcycle by BMW that came with roof and seatbelt, and in some countries that meant a legal problem because BMW didn't want people getting killed with their necks broken by the weight of the helmet.
I'm talking about this BMW motorcycle:
EDIT - I just checked wikipedia and it says the UK authorities refused to allow the use of this vehicle without helmet so I guess things are a bit different in the UK. Still ... one more question to ask to the portuguese dealer if/when I make up my mind about ordering a M3W.
Many countries deemed the use of seatbelts in conjunction with wearing a helmet to be unsafe. The added strain on the riders neck from the added weight of the helmet could cause significant injury to the restrained rider even in a low speed head-on collision.[3] Germany, Switzerland, Italy, France, Israel and Spain authorities were quick to allow an exception to the helmet law for the C1. However, poor C1 sales in the United Kingdom may in part be attributable to the British government's refusal of BMW's request to change helmet regulations for C1 riders.[3][4] Another country that requires C1 riders to wear a helmet is Sweden, although wearing the seat-belts is voluntary.
