This is a great thread, and there are so many tangents, that it would be easy for me to digress.... My rule of thumb is if the bandleaders ego is bigger than the size of the crowd, then forget it.
I've had bad experiences in all original bands (ie~ yoko syndrome)
I've had bad experiences in 50/50 bands (ie~ every player has a different threshold for the material/rehearsals/pay)
I've had bad experiences in cover/GB bands (ie~ months of rehearsals & high hopes only to fall apart after the second/third gig)
The one common factor is that I approached every one of these gigs with an open mind. My bad, so be it.
But if this is round two for you Jazzy, I'd lay down your piece of mind with the other guys... You've been there done that, it was tried and failed, now it's time for something different.