Are they as archival as polysulphide toners? Do they affect the full tonal range equally as do polysulphide toners? Are they the same as Agfa Viradon New? Do they give the same range of brown tones as polysuphide toners? Can they be used as indirect toners? (So many questions; so little time!) I ran out of potassium polysulphide for a polysulphide toner, but have the ingredients for Agfa 120 & 123 and was wondering what I can expect with Ilford MG IV FB and MG Warmtone FB.