Well those Talismans certainly look interesting. Will make buff removers even more important now, nerf or no nerf. I can't even remember where Guard Talismans dropped before the October Tuning Update. I've had only one of them ever.
And thanks for the extra inventory slots BTW.
If you look at the description for the Permadeath effect, you'll see that Permadeath ignores Endure. I found this out the hard way farming Game of Death with Assassin Golden Son. Permadeath also ignores Ghost, which is nice against Magus Lord of Light.
I don't have shells, but I believe Shells reduce damage by 50%, while Guard reduces damage by 25%. Also Shell Talismans last one turn (unless you have multiple sets on a character) while Guard lasts two turns. Guard Talismans are rather similar to the Warrior Troll's Power move, except that power move also separately increases DEF and MR.