Putting aside the practicallity versus looks, the biggest difference is in the height of the centre of gravity.
My experience of E class and CLS suggests that you will find something much closer to a sports car in the CLS and a lot less like a bus....
You can already see the roll transition as the CLS stops sliding and grips, with the 'tall' E class estate it is much more pronounced and takes a couple of oscilations to settle. But that depends if you are going to drive the car to sort of limits that Chris does