I did a summer internship in the summer if 2008 in flight ops for a regional carrier. You will lose time building time, however, it saved my bacon during the recession. I graduated immediately after the summer internship and regionals were shedding pilots left and right. I was able to use my internship to get a non-flying job. While my buddies were laid off, I was still able to bring home a paycheck.
Side note: Due to unrelated issues, I am currently not flying, but again, my internship opened those doors that otherwise would have been closed