[M40i_Nate]

I am buying a 23 x3m40i and it has almost every option available but the sport seats (I wanted red interior so I can live with out that) BUT the one option I really wanted and couldn't find with the color/spec I wanted was the m sport diff. Is there anyway to buy it from a bmw part store and swap it? Does it really make the driving experience better? Am I missing out on much? I drive normally but occasionally I like to have fun and do a-little bit of spirited driving and launching so will the stock diff do the trick? I'm coming from an evo X and know no way in hell this suv will handle as good as my evo did but I still want an enjoyable experience on some back roads here and there.

[ASAP]

I would say the only fair way to answer this is if someone here has owned both or driven both... people speak of their individual experiences but not really side by side.

[BigComfy]

Previous STI owner (2018/20) here. The M40i will make you forget your previous ride 85% of the time. These things are dumb quick and handle surprisingly well for a soccer mom mobile. No regrets minus tire costs. That said, do NOT get the ventilated seat (or at least on pre-face lift). After 3 hours they kill my back. My STI (standard seats) was way more comfy seat wise than the X3 M40i. Handling wise, I'm impressed. About to switch wheels. Stock diff does pretty well IMO.

[bbb83]

For an average joe you'll never be able to tell the difference between stock diff versus m performance one. I would only get m performance one if you know what you're doing and track your vehicles regularly. If you don't, save your money.