I'm not entirely sure why anyone would want to knock up a fake picture of an email from P4U stating the colour of the black IPV4 but feel free.
Because they are selling a unit based on a photoshopped picture created by Asmodus that shows it's all black, telling customers that it's all black, and they could have a lot of cancelled orders and refunds if it's not all black.
I don't see why Pioneer4You would tell resellers in an email that it's all black and then post a picture of a silver unit with a black battery cover and call it a black unit on their own Facebook page. As I said before, the picture I posted and the others in the link I gave are the ONLY pictures of a "black" IPV4 that have come straight from Pioneer4You. I'll take their word over any claims made by any reseller.
BTW, I don't suppose you could post a few of these "bunch of pictures of emails" so I can cross reference the Pioneer4You rep, could you?