I had a studio space in Port Adelaide for a while - used seamless for background and for full length shots. Gray (charcoal), white and coppery tone. Gray was good, because I could make it darker or lighter depending on how much light I threw on it, or how close or far the subject sat for a portrait.
Dean Collins had a great video that shows how you can make a gray seamless any colour you want as well - it was quite a versatile colour.
Still have them at home, stored away - 3 almost brand new rolls. Might have to unload them at some stage. . . . . .