Another great review Dann
I had "heard or read" (can't recall exactly) that the SI Ballistic M-Frame 3.0 had the flattened stems to provide a better fit with the helmets our military use; and it also fits better with the helmet mount for the night-vision goggles.
One other note on the RadarEV, all the lens have built in venting; and the venting design works so much better than the previous method of venting the lens with cut-outs; intentional venting, that works. The EV you get at the top of the lens is great for riding on the bike, when you in the aggressive position on the bike, you are more hunched over and looking through the upper portion of the lens. The Jawbreaker provides the same benefit.