It really depends on whether you're going to sell the cue later or not. If so, don't ever use one shaft. This will make the cue more desirable(imo). To me a cue is worth a lot more if either it has never been used, or has at least one un-used shaft~~just a thought. If you plan on keeping it, I would still hold one shaft in reserve untill you really need it.I.E. having work done to the other or you break it or something. If at that time the un-used shaft has developed a "wobble", call up Chris and I'm sure he'll make it right as any good cuemaker would.
Hope it helps,
David
BTW....what kind of Nitti is it?......his cues are AWESOME......congrats on a great cue.