Maarten Well I don’t know much unfortunately. There are 3 different independent 91mm knives I’ve found that have soft grip scales. All unassociated with each other.
This one that I have doesn’t have a textured feel to it. They are a smooth rubber. If they aren’t looked after or if you use the wrong product on them they get sticky. Like they are covered in honey. Nothing comes off of them as a residue though. I could see cases where this might actually be a good thing actually. They aren’t supposed to be like that. They just have a soft rubber tool handle feel.
The second is a soft grip 91mm knife is from the On the Road limited series. They are black. While they are quite uncommon to find they are actually the most common version of the soft grip knives.
The third version is a red ruby plus scale version.