Didn't know dealers were offering Mobil 1.   I've been using 0W40 Mobil 1 "New Life" (think it's called 'FS' now) in my Ed30 for quite a while now.   The engine just seems to agree with it.   Uses hardly any, sorted a momentary clatter on cold starts and seems to run a bit smoother on it.....and it's £35 from ebay  

I've taken it to the dealer a couple of times now and they're fine to use my own oil.  They adjust the bill accordingly, and pop the left overs in the passenger foot well  

   Which is a good sign as some service centers lob the entire 5L in, which over fills it by 300ml.
The dealer Shell stuff (Ultra AVL 0W30) is actually a superb oil, but mine being stage 2+, it was using a bit of it.
Never really been a fan of oil with 'bits' in it, but the Millers is very popular in the scene.  I just can't bring myself to pay £60 for oil.  Don't need the 'bits' anyway as I've converted the fuel pump to a roller follower  

With the brake fluid every 2 years, it's not essential, but a good idea imo.  The reason being DOT4 absorbs water, and if that isn't flushed out in a timely fashion, it can actually corrode the ABS pump's pistons.