It's not the size of the wand, it is the magic behind it. Large power saws are heavy, and if you are going from the pick up to the pile, well who cares how much it weighs. Generally, the 4.5 cube saws and larger are more BALANCED with longer bars. You get up to the big Stihl or Husky and having a bar under 28 inches is a lead sled. You can cut a two foot tree easily with a twenty inch bar if you have the power and have it set up right. Safety chains while offering a safety kick back measure and smoother running slow down your cutting. Full skip chains are dangerous as can be to the inexperienced and cut like a jackrabbit. Full comp chains cut smoothly and slower.
I have little snotter saws with fourteen inch bars that will out cut something with a sixteen or eighteen that they often come with. I have bigger saws that run up to 42". That means I can cut a six or seven footer with relative ease an safety. People think they need big bars, and you don't. Weight of a saw is one thing if you have it in your grip for a gallon and a half a day. If you are just beavering up stuff for an hour here or there, what's the point?
I know an old guy that is a logger. He said he never ran a saw with a bar larger than 20.'' He told me he took down a tree that was over 5' in diameter with the 20'' bar. I think cutting something that big with a small bar would slow down production.
I agree that safety chains do not sun smooth.