About the green, black and olive green colours
There is only a slight difference between the colours black, green and olive green. I took a couple of photos which show the difference.
On the left is black.
On the top right is green.
On the bottom right is the dark olive green.
If you decide to get the pitch black version, be warned that it will leak its colour to any adjacent raingear. The black Opalo is especially worrisome. If possible, when choosing two-coloured items, don't choose black as any of the colours.