Re: Mandolin strings
Mandolins don't get used in orchestral music all that often. It is used more with small ensembles or solo performances. Also mandolin orchestras. But most every classical mandolinist that I know of use some sort of flatwound chrome wound string. Thomastik is probably the leading string for classical, but many use Fisoma flatwound. Other brands include Dogal, Pyramid Gold, Lenzner, Optima. all variations of chrome steel flatwound strings.
It's interesting that you cited Mahler as an example because one of the few orchestral pieces that I know uses mandolin is the Mahler 7th Symphony.
2013 J Bovier A5 sunburst w/ToneGard
D'Addario FW-74 flatwound strings
Custom Wegen TF180 w/no bevel
1993 Oriente HO-20 hybrid double bass
Small body guitar converted to octave mandolin