Terrain here in Florida is about the same as you described. My Duratracs have surpassed my expectations. Haven't got into any deep mud since I got them, because we've been in a bit of a drought.
They have excelled in soft sand, gripped very well on loose dirt hills and in moderate mud so far.
They're pretty road friendly too. I plan to buy another set after these wear down, but move up to 35s instead of 33s.