My mando takes ball-end (or barrel-end as I call `em) strings. That lets me recycle old guitar strings when the guage is comparable into replacements for single string breaks. I usually break a D string on the mando during a rough gig. An .024 (light G string from a guitar) works great as a replacement, since the fret worn part of the old guitar string is discarded when wound on to the mando.

Only trouble is, the guitar string is already stretched so it makes for a very high tension when reused on the mando, as compared to a new mando D string. But economics trumps finger-ease, come mid-gig time.