Ah, this one take me way back. I picked up this Nightmare from Mikomicon 2009 for a nut-grabbingly delicious $3, though it came without the box. If you checked the link, this figure goes for about $45, so I think I made a small sacrifice.
As you can tell from the picture, this figure is very well detailed. I wouldn't expect anything less of its producer, McFarlane toys, known for its long line of American figures including Spawn, Jason Vorhees, and The Simpsons. However, the rich attention to detail comes at the cost of its articulation; only the beefcake deformed arm is movable at its shoulder, and even then it only moves in a circle. In addition to this, the base is movable, allowing you to position the figure in any way you want. Nightmare also comes with the trademark Soul Edge for more possibilities in posing or losing under your couch, never to be found again. His posing in this is pretty nice, too. It allows the positioning of his arm to make sense no matter how he's displayed (and it also looks pretty badass). Don't let the picture fool you, though; in person, the figure is no bigger than a pencil.
In the end, I would only recommend this to three kinds of people:
1. Hardcore fans of the Soul Calibur series
2. Devoted collectors of McFarlane Toys
3. People who found this thing for cheap
It's a very visually pleasing figure, don't get me wrong. It's just that the price point just doesn't justify a purchase.