A small point, but I wonder why they can justify replacing the drain plug at £2.69 inc VAT when replacing the seal is all that is needed?
As you pointed out in the linked thread, listing the top-up oil, giving it a value, then quoting FOC - then charging for it later??
I bought empty top-up VW packs (complete but without oil) via ebay years ago, I'd think that they would have been supplied by VW for including in their just launched PDI engines that required special oil, but sold on by an enterprising member of staff - so I have one in each car with correct oils - which have changed as cars have changed! Old VW top-up packs have a pleasing "flat" finish which looks a bit better than these ultra shiny modern versions.
One issue that I had with these packs, the one in my VW Passat 4Motion slipped down on to its side unnoticed, I stopped at services on the M6 and opened the boot, it was high summer and there was a strong smell of "new clean" engine oil - not what I'd expect to find in the boot!! A small amount of engine oil goes a long way when the lid slackens in the boot!! (I'm now older and wiser - I will not get caught out with that again)