As to whether the MIPS technology which allows the outer shell to slip relative to the inside of the foam - a little story: I have had a major head trauma years ago and several hard crashes with concussions since. (All wearing helmets.) It is very apparent that my brain is loose inside my skull and that it take far less to get concussions now.

A couple of summers ago I crashed hard going 20+. Slammed the side of my head on the pavement. Apparently my chinstrap was loose because the helmet slid down, nearly taking my other ear off and knocking off my glasses. (A medium quality Bell Influx helmet. I have full memory of my head hitting, then grinding into the road surface. And all the rest of the crash until my brain said 'you really do not have to witness this". As soon as I stopped, I was fully aware of where I was, looked back and the car behind me was right where it should have been. And after, I was fully with it. No headache, then or later. (Broken collarbone, cracked rib and miles of road rash. Thank you brain, for deleting that second.) Helmet had real damage, both impacted foam and abrasions on both sides. (Lots of bruises and road rash on my right side also.)

Two weeks after that crash I read about MIPS. There's a helmet that does what my helmet did without taking my ear and glasses off? I want it!

Ben