I also owe Mack a thanks - i went with the same set up as him (B4s and Eibachs) and the handling is excellent! Although i think maybe Mack has nicer roads than in my area!
For what its worth; I get a little bit of wheel rub on the front wheel arch if theres a bump when going B road speed, if the road is smooth then not a problem. Also the little aerodynamic flap in front of the wheel some times scrapes when going down one of the longer speed bumps you get, or pulling out of a steeper driveway. You do tend to know when you have taken a bump a bit quick, it does feel stiffer but then again everything is fresher!
Not to put you off though as the handling really is so excellent now! And the car sitting slightly lower looks great, not slammed or anything, just the right height.