I have the same antennae. It's between my carpet and the spare tire cover in the back compartment, so I don't get the full advantage of the gain, but it does do nicely! I bought it because my USB modem was inside a glove compartment and wasn't picking up well.
Did you get my post on the ampctrl? It's actually getting better with time, not worse. I still don't have a pop and it comes on before the windows startup tune. Heck, I'm even starting to wonder if it works at all, but if not, my amps wouldn't be on or I would hear a loud pop at bootup.