If you prefer carpeted mats, I highly recommend Lloyd mats. I have their Ultimat series in the cargo areas of the X (rear cargo floor, the level below the floor, the storage well, and the front trunk).
For all-weather rubber style mats, I really like the 3D MAXpider Kagu mats. I have those in the front row and they are durable, easy to clean, and blend very nicely with the style and decor of the interior. The fit is perfect, too.