Those papers are excluded most likely because those papers do not show noticeable change in the hue. The same toner can be successfully used for image permanence purposes.

When using this toner, it is recommended to transfer the toned print directly into a sulfite washing aid solution, like KCHA or Clearwash. This greatly reduces the risk of stain and sediment, and it also allows more precise control of the color by preventing excessive after toning.

The image tends to darken and increase contrast like selenium toners, especially if you don't tone until the image becomes lighter brown. However, this darkening usually take overnight. Therefore, it is recommended to print slightly lighter than you want.