MNPurple,
I would have to agree with Randy on this topic. Chesapeake's are tough as nails, and will work for you longer then you will want to be out. I have trained 3 Chesapeake's and all of them have been completly different. My personal opinion was that the males were more willing to do what I asked then the female.
I also agree that a lab is a wonderful dog, depending on your personal experience with dog's is what I would advise you to consider in picking a breed. If you get a Chesie, lab, or whatever you decide get him/her as a puppy and spend every minute with that dog you can. Get it around lots of people at a young age, and never never never play tug-a-war with it. I have seen that wreck more would be good dogs then any other thing. It teaches the dog at a young age that it is fun to not give you the bird.
You mentioned you wanted a shorthair also... I can't say enough good things about GSP's. That is my breed of choice for upland hunting. I tried to take him out for ducks, but he didn't last long. I got a black lab for waterfowl now. If I had to do it again I would get a Chessie. After training a few of them, the rumors and horor stories have proven to not be true. They are a wonderful, powerful, long winded breed. Nothing is more enjoyable then haveing a dog that is still giving you 110% after a long day on the field, or the water slew.
If it is feesible to you, get one of each. Dogs are a joy to have around.
But remember, if you want the dog to hunt.... tug-a-war is a sin!
Ryan