I agree with GSquared on this issue, but there's something else you can do to assist yourself in making the decision.

Check your network for DBAs who work at the "20% higher pay" companies. If you don't have any contacts who work for those companies, ask them to introduce you to someone who does. Inside intelligence is vital at this moment. You need to get the scoop on the corporate culture and job expectations before you make the move.

There's nothing worse than making a move for higher pay only to find out you can't stand either the company or the people you work with. Or that the job is something that will drive you bananas in 3 weeks.