I have the RE... installed it myself. Shifting performance and precision is definitely better. A weighted knob would further improve the performance but for now I am happy with the mod and having done it myself, I think its worth the price paid.
On a side note. I also had a Porsche 997.1 C2S with OE SSK. Porsches have their own issues. Getting into 1st gear when rolling to a stop was a huge issue experienced by just about every owner.