I am a bit of a helmet junkie. I have a KASK Infinity that I got at an awesome price (Unclaimed Luggage) and a couple of other nice ones. I recently had a chance to test my Smith Rover MIPS with my head. I was going 20+ on a 20" wheel folding bike when I t-boned a medium sized dog.
I apparently slammed down on the pavement with the back of my head. I had virtually no abrasions. I was out cold and had an ambulance ride to the emergency room. I do not know how much time was involved. I was on a rural road - I remember being loaded into an ambulance, which had travel from its base manned by volunteers - and then a 35 mile ride that I have no memory of.
Helmet shell was cracked in a couple of places and the hard foam inner was broken up into several sections. The helmet had no abrasions, but the outer shell has a print of the asphalt texture of the road!
After a couple of days rest and check ups by neurologist and thorough scheduled physical by family doc., I was back on the bike. During rest period I ordered another Smith!
For what it's worth, I am 69 years old.