For me this is not a matter of GAS or dealing with being stagnant/uninspired, but I do agree with the concept that a different set of strings can change the whole vibe of a bass. I spent years not particularly enjoying the sound of my Zon VB4, which ended up being relegated to a backup role for my main band where I needed my basses to be strung up with rounds for the tone that suited that project, and I event went so far as to change the pickups to no avail. Later I threw on a set of Chromes on a whim during a slow period with the band and I instantly loved the sound. Nowadays I have a different bass I can use as the backup for my main band so the Zon can stick with flats.