Eibach manufactures Carlsson springs. I was debating between Eibach and H&R. Eibach was to be comfortable and not lower it as much. But the H&R was supposed to lower it more, have better performance and a 'ok' ride. However, I am very satisfied with the H&R's, that were even cut half a coil.
A pic of my car is posted about 6 main topics below this one and was posted on 12/7. look for the red 'pic' icon. it is blue on 19' and the H&R lower it enough once i cut half a coil.
I just installed a set of Carlsson springs on my C240 recently. It dropped for about 1 in., very subtle difference, and ride is barely affected. I loved it, it's perfect since I didn't want it too extreme.
Which H&R springs did you install, cup kit or level 2? Did you keep the stock shocks and if so were they sport package? Finally how much was the car lowered? thnx.