That depends on what you expect in terms of performance and what you are willing to put up with. I have the light aluminum Comptech flywheel and I am very happy with it. Keep in mind the purpose of a flywheel, however. If you go lighter, the car will be a bit 'touchier' at low speeds and you will have to learn to engage the clutch more carefully at low speeds. That said, I only had to drive mine for a day or two before it became second nature and I did not notice the difference any more.
Also, a lighter flywheel will theoretically make your car a bit slower on the initial launch from a stop, but it will accelerate quicker once you are rolling at all. It is a nice improvement in those situations where you are just rolling along with traffic, then punch it to pass someone.
You might want to check with Dali, as they offer nice packages on tranny's. The nice thing is, he ships it to your door complete, and the entire job takes no longer than just replacing the clutch. This could be cheaper/faster than paying labor to have the gears/R&P installed in yours.