Since I'm sort of keeping this thread as the running log of my car - my Xmas detail is posted here:
http://www.1addicts.com/forums/showthread.php?t=223630
Since my last update I've done an oil and filter change. Car had done 4200km and the oil looked clean and black.
I replaced the oil with Motul 8100 X-Clean C3 5W-40 (BMW LL-04 approved). It was probably a bit heavier in weight than I was hoping, but it wasn't the easiest finding LL-04 approved oil that wasn't Castrol. Anyway I've had good experiences with Motul oil and brake fluid in my racecar so I thought I'd give it a go. As it turns out the engine oil now runs around 10 degrees cooler under normal conditions and about 5 degrees cooler when under "duress". I wasn't expecting that, and for $150 all up it seems like cheap engine insurance.
Tip for those changing oil themselves: yes you need a deflector in place to stop the oil getting above the underbody covers, but be prepared for splash back as the oil hits that deflector real hard..... I learnt the hard way