Hey man...
I haven't gotten many big gigs... But I've played w/ good bands and not so good ones. The (+) part of playing with a so-so band is that, through your creativity and ideas... you might make them better. As chemistry develops, sometimes other musicians want to feed off of that and become better at their respective instruments. Think about a superstar athlete playing with so-so players. Chemistry doesn't Always come but it could spark something. The (-) thing is that your gambling, and that it's a long process sometimes. Patience on your part is only worthwhile if there's growth on the other end (from the other musicians). But even if that doesn't work out... don't stop playin!!!