I have to ask what you are intending to use the baby monitor for. Are you staying in a suite type room (or a DVC villa)? Or are you hoping to put the baby down and then go for a swim or grab a bite to eat?
If you are thinking of leaving the room, I would ask you to reconsider. Do you leave your baby at home and go to the neighbor's? OR down the street? It is not safe to leave a baby in a hotel room by his/herself. Too many people have access to that room.
But if you're just going to be in the living room while the baby's in a bedroom, then I agree that you'll be able to hear the baby fine without a monitor!