I think if u do abit of market research, there's not really much difference between the price of new SKD F10 523i and 2010 E60 525i Sports(used). Both command around RM360k++ and the difference of just RM20k between the an all new F10 and E60.
Performance wise also the bhp difference is around 204bhp for F10 and 218bhp for E60 525i. Hardly can tell the difference if u ask me since I have driven both.
My advise if you're more concern of the engine performance and not so concerned about getting the latest model, you should go for the 530i or 530d instead. Cheaper too...