Have a read on my thread.
The M3 arms are a must do - front for sure, rear if you are going to do rear work (IE: Sway)
The steering is a bit heavier, not bad at all.
The steering is way better, less tramlining... it is just all around better.
The Camber is a must too. Now, if you keep the RFTs, then not sure, if you switch to non-rfts, then you must put more camber on the car to offset the softer sidewalls or it will roll over on the front on hard cornering.
2008 335i E92 Black, Procede Rev 2.5 (11-1 map), BMS DCI, AR Catless DPs, AMS FMIC, Procede PWM Meth, Forge DVs, CDV delete, 230s w/ 235/265 Michelin PSS, Dinan S3 susp w/ front/rear M3 arms (4), Wavetrac LSD, Subframe bushings, Dinan Rear Sway, Rogue toe arms, Stoptech Slotted rotors, Stoptech Street pads w/ steel lines