I generally have them on my head or around my neck.. or on the table at work when not wearing them.
If I need to put them into my bag, its a soft padded Billingham camera bag (with removable/movable dividers). So they fit snuggly with nothing to scratch them.
If I was using a different bag with other loose items around, I'd definitely use the case. Or if I was traveling rather than just commuting.
Also the case can still make the m100s break. It's not a tank.
Edited by Existence - Yesterday at 4:39 am