My uncle just bought a 2nd hand 2010 F10 523i and he was asking whether there are chips for that to boost it to 528i-like power. But isn't a 528i a 4 cylinder while the 523i had the old N52 engine correct? So looks like he is stuck.
He was also asking about the handling. To my knowledge, the 523i (and also the current 520i) doesn't come with dynamic damping control and adaptive ride correct (or wrong)?