FJ, for what it's worth, the faster you push those bullets the faster you wear out the barrel. I know you said you wanted a barrel that will last a lifetime, but I have to ask another question: how often do you plan on shooting it? I would suggest a barrel from, Faxon, Ballistic Advantage, Green Mountain, Criterion, or Aero Precision (who gets their barrels from Ballistic Advantage). To address the SS vs CMV, I say that really depends on you. The general consensus on a good SS barrel is that it will shoot "more accurately" but when it starts to degrade in performance then it REALLY goes to hell. While a good CMV barrel can be "just as accurate" and the performance degradation is more gradual. Remember these are generalities, every barrel is an entity unto itself. About the twist rate, if it were me making the choice I would opt for the 1 in 10 twist. That will allow you to push longer bullets which generally equates to heavier bullets. I say generally because if you choose to shoot gilding metal they will be lighter but longer. Good luck with your purchase and let us know which way you ended up going.