Ewest, I like the Stihl MS-290, the Husqvarna 450, and the Dolmar 510, all in 18" bars.
If you want a 20" bar, move up to a Stihl MS-311, a Husky 455 Rancher, or the Dolmar 5100.
Whatever you decide, make sure it accepts either the .325" pitch chain, or the full size 3/8" chain....not the 3/8" low profile.
I will say, (cautiously) that Stihl and Dolmar saws can sometimes be difficult to start for those suffering with compromised shoulder, and/or upper arm difficulties. They are not the easiest saws to pull through. Some are equipped with compression release valves to enable easier starting.
