You can dial out most of the push with the Koni's alone. You will need negative camber up front no matter what, I have -2.05 on one side and 2.29 on the other. In the rear I'm at
-2 on both sides but on our cars rear camber is scary. The toe is real important. In the rear I have some toe out and on the front 0 toe. I was running toe out on the front but I like it better where it is now. I installed the adjustable camber arms in the rear and the immediate result was a severe lack of traction, especially coming off the turns. The lack of a limited slip makes it hard to get on the gas. Now I have a rear strut bar and it has helped more than I could have imagined. If you get the rear adjustable camber bars be aware that they may creak and groan. Mine do. (I don't have speedybenz's) Also mine are much heavier than the stock pieces. If I were you, I'd experiment with the shock settings. Try going softer on front (I know that sounds wrong) and harder on the rear. When I was mostly stock, thats how the car liked it best. A rear strut bar is a revelation. I never expected it to help but with my collection of parts it made a substantial difference. (Mine was made by a guy on the MB forums)

In summation without knowing all you have done, I would leave the rear alone until you have more suspension changes. If a strut bar becomes available, consider it. The front camber kit I have is with the Mercedes camber bolts. They don't give as much adjustment as the Kmac kit but it's inexpensive. On our cars you can not be on the brakes turning in. You must finish braking a touch early (speaking from my limited experience) My car prefers to be under power in the corners so I tend to brake early and enter the corner on the gas a little. Good luck. (You do have adjustable shocks on the front, right?)

Les