Four Rivers huh. Excellent hunting. I went to college in Warrensburg and we hunted Montrose and Grand Pass all of the time. Grand Pass definately holds the most ducks, but it also holds the most hunters. I would take a nice quiet day at Ralph and Martha Perry CA any day.
By the way Tank, learn the feed call, blow the hail, use everything that you have to get the ducks down. Don't get me wrong, I love to sit in the blind or right in the marsh, but I also love to have to ducks and geese right in my face and don't want to have to wait all day for the opportunity.
I try to be as respectful as possible while hunting public land, but if soft calling and infrequent calling isn't getting it done, you will hear the hail very loud and if the ducks are flying, very often. The guy in the next blind will just have to deal with it. He should have plenty of chances to blow his call while I am loading my boat with a limit of greenheads.