Watched a lefty throw an R43 today. The coverstock looked just like the original Danger Zone - polished  black solid PK18. Of course, y'all knew that already. I paid particular attention to how the ball rolled. It sure looked like a Danger Zone type core reaction. Quick to rev up in the midlane. He was also throwing a Hammer Deal, and the Deal loped a bit longer in the midlane. Since the Deal is a 2.48 minimum RG ball, I'd have to put my money on the R43 having an original Danger Zone core, or something similarly low in RG. My guess would by a DZ core or even an Inferno core. I didn't look closely at the layout or the oil rings. He was a medium speed high axis rotation player, so it was pretty easy to read the inherent core characterisitics.