Elixirs...or the D'addarios as mentioned. An older, delicate mandolin is best with lights, a sturdy bluegrass instrument or bluegrass-style player pretty much demands mediums.

Although I play mostly Celtic style, for which you're supposed to prefer a round-hole A-Style mando for the extra sustain, I played one for a number of years and concluded that a bluegrass instrument is more responsive to my aggressive playing style...so I now play an Eastman A-505 with the medium strings.

I hate changing them and mostly do it when they break, so I always end up with mismatched sets and my "spare" sets have E's and A's missing...is there a cure for this malady?

W-O