a variety of reasons, not the least of which is that I am a bit of a club-ho.
mostly because I don't always have my gamers with me, and the range closest to my work is grass and a bit on the sandy side. I wanted something a little harder and more durable than my gaming set that I didn't mind beating range balls with and keeping in my office, but similar enough to what I have now that the feel change to my gamers would be minimal.
I do like the looks of the S series clubs though and knowing how I am I will probably end up putting them in play anyway. the more the merrier I guess.