I have to push back here because dead oak is dead oak no matter what chain you grab. Once that wood is dry and hard, every saw is gonna struggle, and the "difference" people feel is usually just a sharp chain vs a dull one. Fresno heat bakes those limbs till they're like concrete, so of course a fresh silky feels great, but run a fresh corona on the same 40 and I bet you get the same result. Half the time it comes down to tooth angle and how you hold your wrist, not the brand stamped on the bar. So what exactly did you test, same chain condition on both, or was one fresh out of the box?