I have 1 WMO that I bought many years ago, from a local shop, it's the 1.1a, it had no original box.

Then I have 3 WMO that are fully black, which I bought from ebay a couple years ago from dacheng I think. They seem legit. But they are all black.
They don't have the the grey sides as my 1.1a have (these ones aren't 1.1a, they are 1.1 but they don't say it, I guess they are the ones that came with the original box but he sells them in bulk).

This is how my 1.1a looks like:

http://www.esreality.com/files/images/2006/49959-wmo1.jpg
http://www.esreality.com/files/images/2006/49961-wmo2.jpg

As you see, the base/sides is grey. Notice how the wheel and cable is grey too. This is the most common WMO color set I see when I search for WMO in google images.

Now this is the weird thing. The 3 ones I bought from the chinese ebay seller are completely black. Black sides, black wheel, black cable. It looks kinda cool all slick black. Im just worried it's a chinese knockoff of sorts.

I wasn't able to find a picture of one that is completely black besides this one with the weird logo:

http://www.esreality.com/files/inlineimages/2009/69101-WMO.jpeg

Mine doesn't have that logo, just the regular Microsoft logo, which has almost completely vanished by now, as it typically happens with the WMO, which makes it look even better tbh.

I was just wondering why the change in colors?

The boxed one seems to be grey wheel and cable and I assume base too:

https://www.ocf.berkeley.edu/~joyoung/project/pictures/mouse.jpg

Oddly enough on this picture it looks like the wheel is black while sides are grey:

https://i.ebayimg.com/images/g/99gAAOSwkGVZsB05/s-l1600.jpg

And i've found this box that says "special edition". What's special about it?

https://i.ebayimg.com/images/g/N4kAAOSwvR5aSKfU/s-l1600.jpg
https://i.ebayimg.com/images/g/qJIAAOSwpzJaSKfW/s-l1600.jpg

Let's see if someone can put some sanity on this. Im just paranoid mine are fakes.