I recently bought a System 7 helmet. Will not actually get to try it out until the spring, though, as my insurance is up.
One thing that I failed to remember was that, for whatever reasons, none of the BMW helmets are DOT certified. Further, I was under the mistaken belief that they could not be sold in the US to Americans, but that I could wear it as a Canadian visiting the US. Wrong.
The states do not recognize ECE standards even though they are more comprehensive than DOT standards. If you got caught (for example, stopped for speeding) the roadside penalties vary from state to state but can include a fine, confiscation of the helmet and the cost of towing your bike if you don’t have a spare helmet.
So, buyer beware.