I am planning a weekend for a group of friends, in which everyone has a different opinion on how much is okay to spend for dinner. Therefore, I would like to do on fancier dinner (I think we are doing Herbsaint) and one casual dinner. I am looking for a casual place in the Quarter, where entrees are below $20. Nothing as casual as Coop's or Port of Call, and somewhere that has a good atmosphere. Also, what is the best place for Po-Boy's in the Quarter?