Due to my recent unfortunate dealings with BMW NA and the unprofessional way that they have handled themselves I am seriously considering a move away from BMW. If I were to move to a 2003+ E55 what differences am I looking at in performance? I know the E55 has more torque and HP, but also has an automatic. Has anyone subjectively driven both cars and do they have a firm idea of what the tradeoffs are? I haven't decided for certain yet, I love my M5 but am appaled at BMW's service.