Hi Frazman,.
Sorry I missed your question but if your still interested I have used the sawn for everything from that big fir to splitting 4” pine poles for fence braces... it cuts smooth, straight and square as long as I do my part.
My philosophy is go as big as your wallet will allow if you can.. I never planned to cut anything bigger than 12” and here I am with a 42” fir I had to split with a chainsaw and some leverage from my grapple.