What performance does an Aluminum Driveshaft give?

[lx5091]

I understand the whole weight thing, but being a driveshaft it has the laws of physics on it's side. What I mean is that it's an awefully small diameter thing that is spinning. It's not like it's a paddle wheel from a ferry your spinning that is resisting against something(water), it's more like a pencil in free air. Using this analogy I fail to see a large gain. Believe me if I ever take it out for any reason, I'll probably put in an aluminum, but I would never waste my time, money, or effort on going in there just to do that modification. I don't think it's worth it. I do agree, however that it does offer more rigidity which in turn applies more of your flywheel horsepower to the rear wheels. (the vibration IS the active absorbtion of horsepower, preventing it from reaching the wheels)