Dinan suspension lowers the car around 0.5". People seem to think it yields a good ride quality but for that slight of a drop I would stick to the stock suspension. The Clubsports are adjustable. You can dial in softer settings for street use if you desire. I have no regrets switching from Eibach springs to clubsports (from a daily driver perspective).
'13 SSII M3 Coupe - KW Clubsport 3-way, Akrapovic Evolution, ESS Tune, StopTech Trophy, IND Euro Front Bumper and Gloss Black Mirror Covers, TMS Studs/Lugs, BMW Performance Carbon Fiber Spoiler/Interior Trim/Center Console, BMW Edition Grills/Gills, BMWPedals Extended DCT Paddles, Advan TC3 18x9.5 & 18x10.5 - Hankook RS3 (Track), HRE R40 - 18x10 & 18x11 - Michelin PSS (Street)