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MS200, 372, 066.
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Back before that was edited from MS200, 361, 066 I almost posted that I agreed "with the list above". Am glad I didn't now!
I usually get chastised for saying it, but in my opinion it's wise to run saws with which you can share bars/chain. The reasons are several and should be obvious. All the mid-sized Stihls (up to 066/MS660) have the same mounts. I believe the Husky/Jonsered and Dolmar mid-sized saws share the same (different from Stihl) bar mount pattern.
Up until the MS361 replaced the 036/MS360 (don't know about the relationship between the MS441 and 044/MS440), all the "serious" Stihl mid-sized saws shared a common clutch cover, and one or two of three different-sized fluid tank screw caps, which was always handy in a pinch. (I believe their new "twist-lock" caps are all the same now.)
I'm only singling out Stihl because that's the line I use. I'm sure some of the others have good points along those lines, too.
I think the MS390 is a 60cc saw and the Husky 350 is a 50cc. The Stihl is notably heavier but in all likelihood would need to be carried less for the same work. They really are more "apples and oranges" than not.