I got a new Martin guitar and am sampling the best strings for her. Nickel Bronze strings are one of the choices I will be trying. But it occurred to me to to try them on my F5 as well. Currently I use 11.5-40 EXP's on my mandolin and see that D'Addario has the same in Nickel Bronze, too. I would like to hear some opinions from those who have tried the NB's on their mandolins. The information I've read so far says nickel bronze seems to bring out the "natural" tones inherent the instrument. Not sure what that sounds like exactly, and they also are a bit pricey.