If you lower your car too much, you may want to look into getting camber bolts or camber plates if you end up with excessive negative camber.
What exactly is too much? 1.5", 2.0", 2.5" (Tein S's/Tanabe DF210's/Cobb sport's?)??
Also, maybe you can put something in the FAQ about what springs are "good" and the others that are not. Which springs that will need you to purchase more than just the springs; ie: camber bolts, camber/caster plates, etc.