sandy,

'regular' and 'stiff' are relative terms.  if you're comparing an r vs s in the same shaft, yeah, maybe you'll get a little more distance but your dispersion may suffer more with an r shaft since it's a bit softer and 'whippier'. 

now, if you're looking across a number of different shafts, that's another story.  one manufacturer's r could be equivalent to another's s rating.  and then you have to look at fitting - how much is the shaft tipped?  i play an aldila rip 60 reg in my 913.  but i sport a 3 wood with an untipped oban reflex 6 in a stiff.

if you're looking for more distance, go to a fitter and look at your numbers.  maybe there's a shaft that will increase your carry and lower your spinrate for more rollout. 

fortunately (or unfortunately), golf has become more scientific and with adjustable clubs, there's a myriad of combinations out there for different golfers.  just because you have a ss of 100-106, it doesn't necessarily mean you're pigeonholed into a stiff shaft.

good luck!

-fred

Thank you very much for all your information, I will look into it. 

sandy

I had a driver and fairways in 2007 that had ProForce ATR stiff with soft tip and they actually felt like hitting a regular shaft. 

 I have a driver with a flex and it actually feels like hitting a regular shaft.

With a swing speed of 100 to  105 you should definitely be using a stiff. I swing about 100 with my hybrid and i use an x stiff shaft. i also have an x stiff in my driver and i hit it about 280. i am only 15 so thats why its not quite 300 yet haha. anyway if you do decide to use a regular flex shaft know that you wont hit it any farther and your ball flight could change dramatically so if you currently hit a fade it could turn into a slice or vice versa with a draw.