I spoke directly with the Colorado Elan rep on this decision and this is what was sent back to me:
"The S12 was introduced when Volkl was gaining a lot of momentum with the Supersport series so it went relatively unnoticed. Basically all manufacturers scurried to the table with their version but Volkl invented the category with it's "forbidden side cut," non-FIS approved due to the shape. I always felt the S12 was a strong ski compared to a Volkl 5 star, S12 has a full wood core vs. foam/wood, fusion system vs. Motion, S12 has a sidewall 60/90/60 construction while the 5 star was a capped ski.
You're right that the Ripstick, it really isn't a replacement; my feelings are that category (I call it "race carver") has proven difficult to gain market share due to the reasons mentioned above. Where I see the Ripstick helping is it is a very solid but manageable ski, has full sidewall, fusion pro system; the toe floats but the heel is fixed so you come out of the turn like a rocket. Plus it looks good and has a descent name. It is really a modified Fusion Pro G from last year."
You find that the sidecut of the RIPstick isn't nearly as aggressive as the S12:
RIPstick = 109-66-98
S12 = 112-67-100
And the comparable lengths, 170cm for the RIPstick and 168cm for the S12, should also mean that the S12 will be a bit "turnier".
The comment regarding the Fusion Pro system also concerned me a bit and I'll have to get some clarification. It was stated that the heel is now fixed and the toe slides forward - in my research on this issue and my personal experience, I prefer systems that allow the heel to slide backward or have both the toe & heel slide.
All in all, I'm really happy that I was able to find last season's S12 in the flat version so that I can control the amount of binding lift, delta angle, and fore/aft mounting position. Of course there have been great reviews of the Fusion system and I do intend to demo it.