
Hi again Harry - re. latex, personally I don't know, but I think there's probably different qualities etc of it so I'd stick with the Kong or the cube that's made by the same company (also dispels food) although from an activity point of view I think the original kong is the most versatile.
Perhaps get one attached to a rope too for variety - mine like chewing on things like that, nudging it around, propelling it at high speed across the room

and it cleans their teeth.
Regards, Teri ;)