My god what a tired old debate...from both sides. Do regional pilots possess a skill set that makes them a good fit at mainline? Yes. Do military pilots? Yes. Both groups are equally qualified based on completely different skill sets, and there are people from both camps who, most assuredly, have no business in a 121 environment.
Does this thread need to devolve into a pointless penis shaking "my job is harder so I'm a better fit at Delta" contest?