Thanks for that; interesting to read and get a quote, last service on their system was 27,000 miles (bought at 31,000).
As it happens I did my own 'B' service just after I bought my car 2 months ago; I replaced extra filters which are listed as options, total cost £95 for the (OEM) parts. They quote £657 plus £88 for the dust filter and air filter element total £745.
No surprise that DIY is cheaper than MB I suppose, but being an ex company car driver I'm a bit out of touch of servicing costs. I hope that DIY servicing won't bite me later on, but the plan is to keep the (2016) car for maybe 10 years, so by then I think a big pile of receipts will be good enough for most buyers.
Shame I can't see what they would charge for the gearbox oil/filter change (7G+ box) as I plan to do that myself soon using MB parts for about £170. It's nice to know how much I'm saving when I DIY...it makes the skinned knuckles feel slightly better.