I've owned an E82 and currently a 340i F30 . BMW appear to have got their act together recently and trust me I was a cynic.
The only issue I've had is a misted headlight replaced under warranty so I can't agree with you and say they are crap.The N55 and the B58 engines are superb, the build quality is absolutely on par with the IS I part ex'd before the E87 and the IS I part ex'd for the F30.
That said, the proof is further down the line as we all know but I don't wait that long. I promise to update people when something goes wrong, that said there's a guy on another thread decamping to Alfa, perhaps he will beat me to it