vegasspeed - if you want to close the handling gap between 335 and the M3, you can always get a bunch of the M3 parts put on to the 335. Check out my signature for the goodies I put on. I also did a little write up in the past on all my goodies.
The research was done by a few talented folks on the site (including Harold at HP Autowerks).
email@example.com (1.641 60') - AutoTune 7-27, Race+Meth, Best ET w/ only 80% throttle 1st and 2nd
firstname.lastname@example.org (1.590 60') - AutoTune (beta pre-5-15), Race Gas, No METH
Perf Mods: Vishnu PROcede Rev3 v5, Vishnu PWM Meth Kit, AR Design DPs, AE Exhaust, Helix FMIC, Vishnu DCI, Forge DV, WaveTrac LSD (Best Trap - 124.665mph)