Sounds like what I do. Plus, since I file all my chains on the saw, what would be the point of removing the chain and putting on another just to have to put the chain back on the saw to sharpen it???
Right now I got one 50 cc saw (working on getting another), 2 60 cc saws, 2 70 cc saws, 4 77 cc saws, and 3 90 cc saws. I also have a 50 cc saw and a 77 cc saw apart. So, why would I change chains???
Yes I have converted several round file (RS) chains to square file. You can not convert semi chisel chain (only full chisel).
The angles are kind of easy for square, 45 degrees back, 45 degrees down, and tilt the file 45 degrees (the flat edge resting on the strap on the other side will kinda give you that any way). Then, just make sure you keep the corner of the file in the corner of the tooth, and your stoke is straight. You have to be able to do it righty and lefty, which is what screws a lot of people up. Also with square, you go outside in, not inside out (like when sharpening a knife).