I asked my Mercedes Commercial dealer about the free AdBlue and was told this only applied to non-commercial vehicles. I found it very easy to fill once I had the flexible VW filler pipe, perfect for awkward to access fillers, no mess.With my new Mercedes Frankia the ad-Blue is free at any Merc Commercial dealer for the 1st year. My man will be putting in free for many years to come, and yes it IS purified Pigs Piss.
It is also bloody hard to fill. I have the s shaped pipe and it is still a bitch, thank goodness I've only done it twice since having the beast.