Honestly I don't see an obvious difference that I can isolate to the '12 linkage alone. The entire bike is different as a package. I think you would have to ride an '11 Race and an '11 std or Six Days but with the same fork to draw an accurate conclusion if it would be worth it or not. My '07 Sachs is very good, I run into limitations with the 45mm fork on faster stuff first.
On the '12, now that I have the fork focused a little better, I notice the shock more, and it can use a reduction in HS comp just like every other GG Ohlins/Sachs. The fork also seems to work a bit better with a little more load on it than the 45s on the older bikes.
Is the TTX shock and all the work worth it? Cool project but in the end I doubt it will make you faster. I tend to think it has a placebo effect for the guys who spent the coin, even with the stock valving that can't be right for everyone.