I would stay away from the rock-it mount. I have seen several people on the forums complain about them being too thin. I have the TeraFlex mount and like it. It's allot thicker then the one they sell at Q-tec.
I looked at the Rocky Road one and heard nothing but good things about it. I didn't want to shorten my antenna to run such a high mount though.
I would suggest the Teraflex and a 3 foot Tigerflex. It will only stick above the roof line a couple inches so it not going to get whacked around a whole bunch any how. I can take some pics of the T-flex w/3 foot tiger if you need.