What are the advantages/disadvantages to both? I'm thinking adjustable ones are only needed if the car is lowered enough to significantly change the rearend geometry? I don't have any plans in the near future to lower my GT, but if I do it'll probably only be an inch or a little more. I just need to get the power to the ground better. I plan to take it to the strip sometime in the next couple of months and would like better traction at launch. I'm also thinking about a pair of drag radials, but until I decide if trips to the track will be a recurring event, I'm not sure about them yet. I do plan to add a set of 18 x 9 inch wheels and wider tires, so the extra width may help a little.