I was just now packing things in preparation for guild meeting on Monday (a sewing projects meeting). As I was fitting my Sports 801Bernina (old & heavy) into a backpack on wheels, I thought it might be worth sharing. I also use a 25" carry-on bag to tote my S135 Bernina in. Having the wheels sure makes it easier to take them. I kept looking with wishful eyes at the regular sewing machine carrying cases, but always seemed to have something else I needed/wanted more. I felt blessed when I realized I already had suitable carrying cases on wheels for all my machines.
I put them in with the heavy end down. They don't seem to mind being "on end" at all. I've carried them this way for quite awhile.