Top Gear review sums it up rather better than this but you mentioned the M differential slip diff and the looks but also the M3 suspension, M3 brakes, M3 undercarriage, M3 mirrors, air curtain technology front bumper and that wide track that no other 1 series has with 4 pipes at the rear and so much driver feedback and responsiveness from motor and chassis combined with the smug feel of the interior and the awesome feeling you get when driving the crap out of it oh and also pretty much 6 seconds on Kyalami stock vs stock quicker(heat soak is a bitch), That is about all.:ty: