I installed an H&R Cupkit on my ZHP in Fall 2010 and it has been a great setup so far. A bit stiffer than stock sport suspension, but still very comfortable on my 18" winter setup. Ride is on the firm side with my summer 19's, but that is to be expected. I don't know much about Koni's paired with H&R or Eibachs, just wanted to share my thoughts on the Cupkit.
2005 Silver Grey 330i ZHP, PP, CWP
19" CSL Reps | Hybrid H&R Touring/Sport Cupkit | BMW Performance Intake | BMW Performance CF Strut Bar
BMW Performance Rotors | Gloss Black Roof |ACS Roof Spoiler | 40% Tint | Black Splitters | Black Grille
Black "330i" Badge | LED Angel Eyes| 3K HID Fogs | Clears | Tri-Color Stitched M3 Steering Wheel | Two-Tone Door Panels | DICE