Imagine a scale of conservative EG colors to wild colors, with Black at 1, Dark Oak at 2, Burgundy and Edwardian at 3, Indigo at 9, and Cardinal at 10. I would put Midnight at around 5 and Nightshade at around 6. Both colors are outside what most men would wear to the office in the legal, banking, or consulting professions. But neither of these colors draws much attention and I find them both to be tasteful with a suit and tie. I have a pair of Falkirk spectators in Midnight and Dark Oak, and I feel comfortable wearing them to work. I would feel the same about Nightshade. However, if I had to choose which of the two would be more office-compatible generally, I'd say Midnight. Outside the office, both colors are fantastic - dark enough for night life and special events, but also work well with odd trousers and jeans during the day. Very versatile colors, with a bit of extra interest. Both winners, with a slight nod to Midnight. I hope my comment is helpful.
Thank you all for your opinions! Here is my two cents. Nightshade changes a lot between indoor light and outdoor light. Indoors it looks rich and sexy. Outdoors I really like it with lighter gray pants. Midnight can be subtle depending on what your wearing but then it catches your eye and it just pops. Maybe we need both colors in our future orders.