Griff,
I hadn't thought about chain stretch. Rick and I were thinking that the V2 actually lasted longer. The V3 is designed for less rolling friction hence we decided that the X rings must be different (didn't seal quite as well). ???

P.S. We aways used to buy the V3. Recentlyjust the V2. I just put a V2 on my KTM 690 Duke (single). It should be OK on that!