I knew that until 8/01 there were 2 types of shocks and 2 types of springs.
Per my research, the M sport suspension was an option part of the M tech package.
As of 09/01, the M sport suspension was standard.
I had the M sport suspension on my car and so did my mom. I have a 99 323i and she has a 01 320i. Her car, OEM to OEM, always felt stiffer and more responsive.
Thanks for the help, it confirms exactly what I thought.