jjrodger
I agree with you, when i try to push the car at high speed cornering, it performs better it terms of you just feel they sway not that abig a deal anymore, because probably the rear of the car sway faster, compare you try to corner at low speed.

I have had tried mycar at high cpeed curve couple of time to do this, The rear tire won't slide of the track, especially with stickier or wider tires. But when you have stickier tire/wider tires this is when you feel the most swaying, because of the tires tries to hold the rear of the car on the track , but the suspension movement not linear when it hit bumps. (I think this why my friend E-class has worse effect than mine, as I describe above).
Anyway, eventhough this swaying is bothering , but the car is pretty much stable during high speed cornering (it is capable).
I just found this annoying, because I also own a E36 BMW 3 series that I had for almost 4 years now, and I like to drive fast especially during cornering. I use 235/24/18 and 245/34/18 tires as well, but the handle just soo tight no left-right swaying movement at the rear at All..!!
I reallty hope that we can find something/someway to correct this swaying movement on the back.
And by the way I think I will try Mbenz solution by using koni adjustable shock. And I will set the rear shock stiffer that the front. I know this will make the car tend to oversteer, what I'd like to know how much can it help to correct this swaying symptons.