Hello,
I've seen many debates on this issue, but here's what I intrpreted over all.....
A cold air box is just as efficient as a ram air setup on the S/C GTP because of the blower. The air is not getting "rammed" hard enough to make a difference w/ the super charger that already mechanically rams the air in. Unless you're doing 100+ mph. Even then, the air seems to get deflected over the hood at highway speeds, you can watch the raindrops on the hood, they don't seem to move very fast., I believe there is no benefit to a ram air hood, vs the cold air box.
On the other hand, I love the look of the ram air hoods, especially the ones w/ heat extractors. So, if nothing else, you can do it for looks.
Later now,