I have a Kellam Slasher which I consider a Leuku/Puukko hybrid in that its thickness and width of the blade and handle are more in line with a puukko but its length is 7".
Its my favorite knife, used it for chopping, carving, peeling bark away from trees looking for grubs, digging edibles out of the ground... a ton of stuff... even "battoning"(if one considers making kindling out of 1-2 inch pieces of wood battoning. Also used it for carving up cattle etc... The lightness of "rat" tang knives allows larger blades to be used for things you would not consider them to be efficient at... such as processing poultry or rabbits.
Oddly it has not broken(sarcasm), guess I'm not using it right... never once hit the handle with anything other then my hand.
I am sure however that the day I do is the day it fails me.
I've always wondered about the Leukus. I've never been a fan of knives in the 6-9in range but they seem to do very good work