I have both the OB Classic and SS360. The OB is a really good shaft, but the SS360 is even better. It transfers more energy to the cue ball, and has much more feel. There MIGHT be a better LD shaft than the SS360 out there somewhere, but my search has ended.
Be warned, once you try the shaft, it'll be difficult to resist ordering a complete cue. Mine works well with a number of butts, but Bob's 6-pie laminated cocobolo has taken it to a whole new level.