The training's good, and either rating (737 or A319) are very useful, and the money will be cosiderably more than you're on now, so take it and put up with awful conditions until your bond is up. At that point, for your own sake, find a real airline and leave. If something good comes up before the 3 years are out, leave anyway and pay off the bond. Whatever else happens, you won't want to stay long.