Not speaking from direct experience, but you're better off saving your sheckles for some other performance modification (like changing all your fluids over to synthetics and getting a B&M shift kit).
With the cost of the hood and getting it painted, this won't be cheap -- and the performance gains, to me, are negligible unless there was duct work feeding directly into the airbox along with an ECM tune to handle the increased flow rate. I don't see any mention of any Ram Air-style duct work. You'd probably get the same effect by yanking your factory hood plugs out.
Xman knows what's going on. I'd do his mod and see how that works out.
Congrats on your new GTO!