Worth bearing in mind that if there's the slightest chance you might race one day, buy a helmet with HANS posts since wearing of a HANS device is going to become compulsory from 2016.
Closed car with airbags and 6 point harnesses - I wear an open faced Bell Mag 8 and use a Scroth HANS device and would happily recommend it as a setup for anyone with a head that fits comfortably.