From all of my experience lowering vehicles it does matter if you change out the shocks. the rod that makes up the center of the shock has a certain range that is for stock suspension travel. If you lower your vehicle and leave the stock shocks you have placed you shocks toward the upper end of the load range for the shock at normal ride height. This doesn't leave much room for a progressive shock or even a gas shock to absorb your impact. So when you hit a small bump in the road the suspension take more of a jolt and can bottom out than it would if it where one made for a lowered vehicle. Yes the shock would be a little stiffer but the way the vehicle will handle in turns, on rough road, and during emergency type driving will be much more favorable for the driver than with the wrong shocks. Hopefully this helps.