Limited Editions Club recommended a product called "Leather Vita"

Someone is selling a Limited Editions Club copy of Grapes of Wrath. There is a page included with the books that calls for using a product called Leather Vita to keep the leather supple. This page was produced by the publisher. I have seen a lot of debate here about whether to treat leather with anything at all. Some saying to just leave your leathers alone and apply no product. Some debate whether you should even cover the leather in a mylar cover. It seems this publisher though that leather treatment was appropriate at least on this type of leather. I wonder if it would also be appropriate to apply this product or others like it to the sheep skin leather that so many people have a hard time maintaining.

https://i.ebayimg.com/images/g/HsoAAOSwfRZfMY3E/s-l1600.jpg
https://www.ebay.com/itm/Grapes-of-Wrath-John-Steinbeck-1940-Limited-Editions-Cl...

The leather on this edition is actually rawhide. I don't know what is in Leather Vita, but I come from a horse tack oriented point of view, and rawhide is not treated with the same type of leather balm as tanned leather.

Here's an interesting discussion on how to treat rawhide tack. Horse tack is going to get dirtier, wetter, saltier, and used a lot harder than the rawhide of this edition, but I think it's a good guide:

https://elvaquero.com/care-and-treatment-of-rawhide-gear/

(your option to use beef liver, raw brains, or calf testicles, by the way).