A 20" bar without much troubles? Can breeze through some wood? Burying a 20" bar in hardwoods is a job for a 60+cc or bigger running 3/8" pitch chain. Can lesser saws eventually get the job done? Sure, but they can't meet your requirements. They just don't have the grunt. It may not fit your situation, but I agree with the other posters who advised to save a little more money or look around some more.