(Selenium) toning variable grade FB paper Fomabrom Variant 111

I got the opportunity to do a little exhibition of some of my large format (4x5) black and white work and even to sell prints at the gallery. Due to budget reasons I need to stick with paper that is less expensive. And here in Dresden, Germany the least expensive paper to get is Foma Paper (Fomabrom). So I want to make the best possible (40x50cm) prints possible with Fomabrom paper.

I have never really toned any paper. But I have read that toning (especially selenium toning?) may improve the look and also the archival qualities of a print on FB paper.

So I have some questions:

1. How variable grade paper, especially the Fomabrom Variant 111 paper react to toning?
2. Is it worth it?
3. Does only selenium toning improve the archival quality or are there other toners with the same impact?
4. Does toning variable grade FB paper differ from toning fixed grade FB paper in regards to visible and archival qualities of the final print?

1. I've always toned Fomabrom Variant 111 with selenium, but I'm going for archival qualities vs any tonal change.
2. IMO, yes.
3. I've only used selenium or sepia toners, but I'm sure other toners will provide archival qualities.
4. I've only ever experienced differences between paper manufacturers. In my experience, some papers will tone beautifully while others seem to have little effect from toning; I'm taking selenium, only, here.

Other than gold it is my understanding that selenium toning is best for archrival. I tone both RC and FB for permanency or archival storage, but not so much for the change in tone. I used both Foma FB and VC, no issues with either. If you are selling prints I recommend processing for permanency, when I was showing and selling it was a common question asked by buyers.

Actually, sepia toners provide better longevity than selenium, unless you are willing to accept a significant change of image colour from selenium - partial selenium toning doesn't provide full archival benefits.
I always recommend that people concentrate on the image tone properties of toning. Longevity is best achieved through complete fixing, and complete washing, along with the aid of washaid.

If you want full protection that selenium toning can provide, you will get a good deal of colour change which may not be desired. I only selenium tone enough to improve the DMAX of the print and then finish with Ag Stab (Sistan). Of course all the toning in the world is of little benefit if proper fixing and washing has not already taken place.