I think the rod bearings issue is really exaggerated. I ran one for 8 years so spent alot of time researching issues etc and appears to be more of an issue in the US but still not something that really happens as often as is made out. Knew a BMW service manager who said he had 30 on the books at one time or another and hadn't seen it happen on any.
That being said a well minded car with full history is a must, it appears that it is caused by ragging the engine from cold so hard to tell but oil analysis does throw up if there is wear.
Apart from that the actuators went on mine and that's it, I put about 80k miles on it in that time. What an engine.