Wow you did get some terrible advice in the engine subforum ... ignore it!
Agreed with Peter that track-oriented brake pads are a good idea if you have track experience. The OEM pads work - I'm surprised how long my lasted given how hard I abused them - but aren't in their element operating at very high temperatures. The stopping distances they provide just are not precise.
2011 BMW E92 335i, 6MT, Le Mans blue - Quaife LSD, JRZ RS Pro, JRZ camber plates, Eibach ERS, full M3 susp, custom toe arms, Powergrid end-links, SS brake lines, brake ducting, Michelin PSS, UUC SSK, ETS FMIC, ER CP, Perf. Exhaust, VAC RSIK, Sparcos; work by VAC Motorsports in Philadelphia