I think it's a good investment.
But this is coming from a guy who is very critical about weight.
The less weight, the better. The car brakes better, handles better, accelerates quicker. But, you would have to take more weight off than with the hood alone.
Carbon Fiber hood + Lightweight wheels + remove backseat (if you desired) + get rid of all the junk out of your car = a good start.
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