I'm a chainsaw guy. Of the 3 you listed, all are great choices (STIHL, and not a pull-on or homelite), I'd suggest the 260. Because it is a pro model STIHL. 270 and 280 are good saws, but if you are going to be heating with wood, or using it a lot, go with the 260.
I have a STIHL 039 (MS390, now), 011AV (old saw, small, similar to 009), Olympyk 934DF (arborist saw), and a huge old Homelite from the '60s that I was given. My dad has a STIHL 038AV (I wish it had an 038 instead of my 039). A friend has a STIHL 044, 041, and an MS210.