I see this thread got bumped from the past. My post up above was two years ago about my wife's E90 330i and how reliable a car it has been. Nothing has changed in that respect! Two years later the car now has 108k miles on it, and it has only had one non-maintenance issue in that time which was a camshaft position sensor. It faulted one time and then ran fine (using Autoenginuity to read the codes), but a new one was put in anyway as it's time for those to be proactively replaced anyway. That's it. Other than that all I've done is change the oil every 7k miles, brake fluid every two years, coolant every three, etc, and it's past time for it's 3rd transmission fluid change, so I'll take car of that shortly (I can't fathom someone adhering to BMW's "lifetime" transmission fluid bs). It will be 7 yeas this December since we put in the order for that car.
Word-up, my friend. It IS BS, plain and simple. Yesterday I had my 330i at the dealership for an oil change (after 5000 miles) and the service "advisor" looks at me and says incredulously "You want an Oil change? You're not due for another 10,000 miles!". I said "Yes, I want one NOW. Old-school maintenance, my friend" with a straight face. He replies "Well, BMW recommends a change @15K...but there's a lot of people out there like you who still change the oil after 3-5k - it can't hurt, you can never change the oil too much". Thanks, "Captain Obvious". Plus there's the little matter of not wanting to be at your service desk a few years from now pricing a major engine overhaul and wondering why I didn't change the oil more regularly!
Actually, it's not BS at all. The factory fill fluid will last exactly the lifetime of the transmission or differential. On another note, it's "nice" how BMW eliminated the drain plug on the differential in the E90.