If you talk to 20 different guitar players, you could get 20 different opinions about how often to change the strings on your guitar and also, what the upside or downside is. There is no right answer.
Some guitar players love the sound and feel of brand new strings and change them often — as often as before every show.
The upside is that the strings will have a more active response to your touch. Once in tune, they’re more likely to play in tune if the intonation of the guitar is good. The downside is they are more likely to go out of tune until they’re truly stretched out, and some people find new strings are too bright.
Some guitar players love the sound and feel of older strings and resist changing them. The upside is that the strings will be broken in and since you’ve played on them a lot, you’ll be very familiar with the nuance of their response to your touch. The downside is that they are more likely to have intonation issues, even if the guitar is set up and adjusted properly.
There are times I hate to part ways with used guitar strings that feel great to me. You’ll have to decide for yourself based on your own experience on stage.
