Thanks Jerry
I've the Simpson device on order and should have it to try out by the weekend. My current helmet is closed faced so I'll try with that first and see where I end up. I need to change the helmet anyway as it's out of date so I can evaluate open face options at the same time. I'm not seeing how open vs closed face makes a difference for maneuverability though?
I did call Simpson before ordering - it is designed for 3" straps (simpson hybrid sport) and I'm only planning on track days so that aspect should be ok (I hope)
I'll update again later for benefit of others