BTW, [MENTION=198600]Witterings[/MENTION], if your helmet hit the deck, get a new one. It did its job.
After witnessing a horrific crash during a large group ride in July I went shopping for a second helmet. The guy's right side of his head smacked the pavement, then he slid headfirst at 20+ mph into a curb. Crushed the helmet in the occipital region -- rear to one side. Caught it all on video, but I haven't shown it to him. Too stressful while he's recuperating.
I have a Bell Formula MIPS that's very good -- excellent attention to detail, reasonably lightweight and well ventilated, and comfortable. Really a bargain at around $70 US -- it looks like a much more expensive helmet. But I've always worried it doesn't cover quite low enough along the occipital region.
After shopping around and trying everything I could find, I got a POC Omne Air Spin. It's basically a well ventilated, lighter weight version of those hipster skater/commuter helmets that are so poorly ventilated and look like bowling balls. But POC got it right. It's much better ventilated and cooler than my Bell, with vents that scoop air across my scalp -- I have long, thick hair and I can feel air rushing across my head even in hot, humid Texas summer. The EPS foam is thicker than most, especially in the back, and it covers lower around the ears and occipital region. POC's "SPIN" is just a simplified variation of MIPS, to allow the helmet to deflect while the harness grips the skull and keeps the helmet in place. Dunno if POC's SPIN works but MIPS definitely does (I was konked on the noggin by a railroad crossing arm a few months ago and the Bell did the job).
A couple of drawbacks to the POC. The thicker EPS somewhat obscures my forward view when I'm in the drops -- it doesn't block my view of the road, but there's an overhang above my brow that's noticeable. A minor nit, but worth mentioning. It's a little heavier than my Bell helmets. The "Y" harness strap is not adjustable for length around the ears -- I had to scoot the Y harness doodad forward a bit to relieve pressure under my ear lobe. It's fine now. The chin strap length is conventionally adjustable. But folks who prefer to pull the Y harness way down toward their jaws, away from their ears, will find the POC to be unusual.
Anyway, POC makes good if pricey skull shaped styrofoam beer coolers. Probably a little better protection than some. The Omne Air Spin doesn't look quite as odd and bulky as the Octal. It'll be my casual riding helmet now. I might consider another POC for my road bikes if I can find one without the brow overhang.