Another vote for modular - like two helmets in one
Helmet for around a hundred
http://search.ebay.com/vega-summit_W0QQ_trksidZm37QQdfspZ32QQfromZR40QQfsprZ1QQssPageNameZWD8Bhttp://www.webbikeworld.com/r2/motorcycle-helmet/vega-summit-II/I have only good things to report from having one of these for 21,000 miles. The innards are adjustable via adding or removing foam or similar material to the removable padding pockets.
As a geezer in training, I run with a wind shield most of the time. I can ride with the helmet hatch open at 100 MPH with no helmet vs. wind issues.