The South Florida 9/10 crew seems to prefer the standard Double Bubble, and I don't think they would be using it unless it improves the top speed.
I have two different clear Zero Gravity Double Bubbles. I have the regular one like everybody else has, and then I have the "Low" version (also referred to as the "Drag" version). I like the Low one better. Either way, you can see your turn signal indicators without stooping down, and you can see through them. Especially the clear one. No more "Fun house mirror" effect like the stocker.