Just for my two cents, I was recently fitted for a new driver, the TM Burner TP, 9.5, 50g stiff. I spent two days with the launch monitor to see if the numbers were consistent. They were, to a certain degree. The first day resulted in the fitting. In the second day, my spin rate was considerably higher but so was my swing speed. In other words, I was swing harder duiring the second session. The fitter and I agreed that the first day was a better swing as my contact was better, so was my tempo. So, if you think your new harder swing is going to be your "new" swing, I would suggest that you get fitted before assuming that the new shaft will be the answer. Otherwise, just slow down a bit and put more balls in the fairway.