The YS-6 is still a good shaft -- GD is still selling the YS-6+ so it's not like a whole lot has changed. Grafalloy is still selling the ProLaunch Blue and Red with mostly cosmetic changes, along with the ProLite 35. If it still feels good and your good drives still look good, no reason to change. If you're itching to try something new, that's one thing, but I've been recycling my shafts for years, still using some older Oziks, which have to be from 2007 or 2008. People will tell you to get on a launch monitor, and a salesman will tell you the latest and greatest $300 shaft is right for you, but unless you're going to see 10+ yards improvement, I wouldn't worry about it.