The bobbins are 3 times as large as normal domestic machine bobbins. It's really not an issue to change them, because you do it less frequently than on other machines. There's a window to look through in the extension table that makes it so you don't have to remove it to change the bobbin, but I usually do as I have a hard time working around it.
Honestly, this would not be my major concern about choosing between the two machines mentioned. I would be waaaay more worried about the repair and history of problems of each model.