I've had my sportlines for about 6 months and the passenger side is 3/4" higher. It looks as if I where a Fat Ass, but I only weight 150lbs. The place I bought them said they needed to settle, but they still are uneven. I don't drive the car that much, so I figured that was the reason for not settling. This weekend I'm going to disassemble the suspension and compare spring heights. If I can see a difference I'm going to return them.
I think Eibach has some quality issues because since i've had this problem i've noticed many other having the same problem.