You can also mix gauges to adjust the feel of individual strings or build a custom combination for a particular tuning. We make nickel wound and stainless steel wound loop-end banjo singles, so you can control both gauge and wound-string material.
When building a custom set, remember that gauge, target pitch, scale length, material and construction all affect feel and response.
Banjo string life varies a lot from player to player. Stainless steel wound strings offer good corrosion resistance. Change strings when you notice changes in tone, feel or intonation, or visible corrosion.