Try on the Rage from Simpson:
Simpson Hybrid Pro Rage Composite Head Neck Restraint
I tried the various alternatives at the past two PRI shows, that one seemed to be the most comfortable yet secure for me. The only drawback was that they want me to start with the fixed tether version, adjust it, then send it back to them for conversion to the sliding tether version. They said it makes sure they get the adjustment range correct for the slider that way.
a3ftgiant, what kind of vehicle were you using one in? Was it the sliding tether version?
Incidentally, if you plan on running any Top Sportsman racing with a fast diesel (like I plan to with my new truck), a restraint system is required starting this year.