A related aside to what Notes just added about making parts for certain people. In addition to transposing instruments that may make switching from flatted key signatures to sharped or vice versa, you can run into the personal preference.

Here’s an example. I double on vibes. With my limited skills, the bar that is F# is always F# in my mind no matter what the key. Sorry, but I have enough to think about hitting the right bar than to read a correct enharmonic of Gb. It’s just not going to happen. Now, put a trumpet in my hands and I’ll read whatever and expect it to be enharmonically the ‘right’ spelling.

BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.