I posted this in the DIY forum but I thought this opinion may deserve a wider audience (sorry for the repost).
I contacted a reputable local shop that does A LOT of work on BMWs (
http://www.landsharkautomotive.com/) to do my mid-period oil change at 7,500 miles because they would do it for less than the dealer. I was told by the owner that I should stick with changing the oil at dealers. He said these are new engines and I don't want to risk being excluded from some potential recall/repair on these engines because I wanted to do my oil changes on the cheap. He basically turned away my business for that reason and I respected them for it.
Take this for what it is: one BMW mechanic's opinion. Of course we could disagree on whether this would or not be a problem, but the way I see it, the MOST anyone could save on the additional oil changes by doing them him/herself with BMW parts is about $40 every 15,000 miles (assuming you're doing them midway between factory-recommended changes). This seems HARDLY worth it even if the risk is quite small.
YMMV.