B,
I'm a VA resident (northern VA), but I hunt in MD too. I"ve hunted the Patuxant, lower Potomac and some on eastern Shore backwaters. started out with a 15' modified-V aluminum jon; traded it for a 14ft TDB classic. Although I don't hunt the open waters of the bay, i would feel comfortable doing so in the TDB under most conditions, but not in a flat bottom jon. one wave over your bow could swamp you. The flat bottom sounds fine for the rivers and backwaters, i wouldn't recommend it for the bay. I'm relatively new to this game, so you might want to contact some local guides to learn more about the different types of hunting available (puddle ducks from boat or blind, sea ducks from layout boats, body-boot'n, etc).