Your PE sounds great ... excellent choice! I wouldn't know when to shift if I had the stock exhaust, it's just way too quiet.
BMW Performance FTW ... it's expensive but OEM quality is nearly unbeatable, perfect fitment, and it counts as an "accessory" as far as warranty is concerned, not a "mod".
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