always buy bilstein for mercedes. yor ride will be different using any other brand. It will not handle ike what you are used to. I think the E420 or any other w124 comes with the HD bilstien. If you want better handling get the sport bilstein. I changed the suspension on the 300E with the sports and h&r springs, great handling. My stock E420 rides really good nice and plush for german standards but handle is not as good as my 300E. I can goo faster around the corners than the E420. Then sports will be stiffer, but only really noticeable around train tracks and pot holes. I live in san francisco and there are more pot hole than gopher hole in any city park. I call it pot hole city. Then choce is your comfort or handling? OEM is HD bilstien.