Okay so not sure if this has been answered yet. I've spent lots of time trying to figure out what the difference between the sport suspension and non. At the end of the day, the dealer had no clue. One dealer who does performance installs tried to sell me a dinan which my forum friends here told me to get away from.
So far what I know:
Guide rods (the hook looking things)
You will need an alignment ( a bitch with active steering)
Anti roll bars are different too
Really the ZSP is the best money any BMW owner can spend. My car goes back in 2 weeks and I will not get another BMW without zsp, you also get tighter steering ratio: Fat steering wheel, compatible with later swapping to M sport or others, and some bad ass seats that hug you tighter than a gold digger after winning the powerball!
So don't skimp out on suspension alone, thinking I could retrofit....and I DO REGRET IT! too many parts, never did the mod and my car feels like a bus compared to the zsp's I've been test driving.
Happiness IS the corner!