I meant arbitrary in terms of these sudden and late breaking changes. A helmet that was good for years (as of June 13, 2015) is now being obsoleted much earlier. What if I had bought an M2015 helmet in the last 6 months? Or an M2010?
I did just buy a M2015 helmet after waiting all season to get something that would be up to date and last for a while given minimal abuse of ~10 events per year.
Via the Snell Website:
"What are the differences between the SA, M and K standards?
The SA standard was designed for competitive auto racing while the M standard was for motorcycling and other motorsports. The K standard was released to accommodate helmets used in karting. There are three major differences between them:
The SA standard requires flammability test while the M and K standards do not.
The SA and K standards allow for a narrower visual field than the M standard (Some SA and K certified helmets may not be street legal).
The SA and K standards include a rollbar multi-impact test while the M standard does not."
I think the argument could easily be made to ASN that unless all SoloSport is going to require prep including fire suppression and roll bars, there is no sense in going to SA-only helmets. That certainly goes against the whole point of SoloSport's accessibility to Average-Joe.