In the first post he says his band is going in to a studio. Not sure where you picked up the paid session work.
Ditto. I remember OP stating he was a part of the band, not just a hired gun. And if that's the case, he should use whatever bass he's been using to this point because it's part of the band's essence.
Unless of course he likes the jazz' sound and he'd rather just run with it anyway. In that case, whatever.
+1