Since I've never seen one figure I'd start a Randall knife thread post your stories, pictures, and anything you've got to add. Here's my pair of Randalls a stainless model 1-5 and a model 18 attack survival.
I would say that the saw teeth on the model 18 aren't best suited for wood they work but aren't the best. They probably work better on aluminum as that was the original purpose of the knife was aircraft survival
I had a model 15 at one time and I'd agree with you there the guard did get in the way sometimes. Something I noticed about the model 18 though was that although the sawteeth cut very well the blade was so thick as you got towards the center that it didn't want to cut any deeper. Other than that it worked great