The modern gas chainsaw is a far different animal to its predecessors. The new way of doing things is all about chain speed and high rpm. Old saws are a lot more forgiving as far as a poorly sharpened chain. They had chain speeds of about 1/3 compared to the new generation saws and they would almost pull through anything and were far harder to bog down. The new fast high rpm saws need almost perfectly sharpened chains or they will not perform well. Its not that new saws are more powerful in terms of H.P, they are just faster and providing your chain is on the money will cut wood faster. The old saws had longer cylinders bores and max rpm was a lot less. lf you know how to file/grind chain well the modern chainsaw will get more work done faster. Just my 3 cents.