I've experimented with a few different driver shafts and have switched adapters on stock shafts to fit other manufacturers. Pretty interesting when I got fit the fella basically said that there were 2 stock options and one would be better than the other and then simply said, "or you can go boutique." I'd bet of all of the players that would self-identify as a "golfer" nearly 99% play a stock option.
I've been considering something new and want to go hit my head on a bunch of shafts on a monitor sometime soon. Live in a small market so it means travelling.