1. about an inch front/rear
2. great improvement in ride handling and feel. To be honest I did the wheels and suspension at same time, so I can't tell you which had more of an effect.
3. All I did was buy the kit **********s and have it professionally installed. As far as I know, nothing else was needed (if it was there was no mention by my installer(.
2008 Monaco Blue/Tan interior 335i sedan. Mods: AFE intake w/ scoops, AFE Exhaust, ER FMIC, Koni FSD/Eibcach Pro-Kit, Breyton Race GTS wheels w/ Continental ExtremeContact DW tires, Cusco OS strut bar. BavAuto Black/Beige seat covers w/ black floor mats, M3 rep trunk lip, eBay front splitters.