Go for the 240 and keep the CF and racing-sheel seats off the 335! IMO, the effort put into the 335 will not yield the preformace benefits you are seeking compared to getting a track car and you will take some class away from your daily ride. But hey, if you like the racer look for your 335 then go for it.
Arctic/Blk Leather/Alum.Trim/MT/ZSP/Sunshades/Blk Lines/M3 Illuminated Knob/Alcantara Performance Wheel/M-E-Brake Handle/Euro Fog Switch/Koni Yellows/H&R Sport Springs/19" VMR V718's w/PS2 Tires/M-Tech Body Kit/Carbon Fiber Spoiler/Bimmian Interior Bulbs/OEM Eye Glass Tray/SSK/Alcantara Boot/Split Armrest/OEM Dual Rear Power Outlets/Rear Ashtray Delete/OEM Alum. Pedals/Osram 6000K/Brex Rings/LED Side Markers/BMS Power Box