I bought my slingshot for the freedom and openness - every single optional safety device, be it seat belts, 4/5 point harnesses, 1/2 helmets 3/4 helmets, full helmets or hans devices, all of them reduce that freedom a bit, the more safety coverage the less freedom & openness
how much of that freedom & openness you want to give up so that you can feel safer is a matter of your choice and perhaps local laws.
I try to keep the openness and freedom to the maximum amount I can as such I use the lightest and smallest 1/2 helmet I can find I do this because the law requires a helmet, On the other hand I do not use the factory seatbelt/shoulder harness, In California under the mandatory seatbelt law they specifically exempted motorcycles so legally I do not have to wear a seatbelt, but I do have a lap belt I installed that uses the factory buckle - I do use this and I wear it by choice to keep me from being ejected, God willing.
These are the choices I have made and I am comfortable with them - -
all of you, my friends, can and will make your own choices and whatever you choose, I will respect. It is not my place or for that matter anyone else's place to make these decisions for you
As a side note I must add that if I do see you riding around town in your Slingshot wearing a hans device please forgive me if start laughing - - - sorry