Waiting patiently for my M3W to be manufactured and shipped to Madrid, I've being looking for a helmet too…
When you drive in the motorway or small roads and see the amount of insects splashed into my car's windshield, I'm convinced I should wear a helmet (sorry but I'm not a hungry Mexican who likes eating grasshoppers and other kind of bugs).
And a few months ago my windshield was hit by a Stone lifted by a truck in Front of me, and broke… so unless you drive the city, I guess it's really a safety rule to wear a helmet!
The ones I'm about to buy are the Nexx X70 Groovy, a jet helmet with full face screen and sunscreen too. Beautiful soft genuine leather trim and they are prepared for intercom installation (very convenient to hear your smartphone GPS instructions, music or phone calls).