Buying a new helmet

I currently have a Momo open face helmet like this http://t2.gstatic.com/images?q=tbn:nGqC1rfd_PhUmM:http://ivaluemyhead.com/product_images/fighter_red.jpg&t=1It’s a few years old now, so time for a new one, but I’m not sure what to get. I ride a vintage vespa, so open face is the way to go.I don’t want to pay the price for a ruby helmet, also I saw someone with a stripped one (like the group logo) and it looked a bit ridiculous. Does anyone have any ideas?