Joey,
I cut a lot of water oaks. The unfortunate thing is that the large ones are not only time consuming on the mill but are full of bug holes and rot. The wood you can get from these trees is quite pretty though and, because it is so available, the backyard woodworkers here have me cut all they can find.
I have cut limbs that were of good size and the craftsman will pick the good stuff out of it when dries. Limbs must be cut like you would a leaning tree and have the stress relieved from the cant as it is cut.
Water Oak is one of the Red Oaks and is course in grain. Its rays, when quartered, are large and crotch wood is almost luminescent. There is a tendency for some of the grain to be black and this red and black combination is desired by many of my customers. I don't know for sure, but I have been told that the black streaks are bacteria infection and cause the wood to separate, something I have not experienced.
When you are approached to cut any type of wood that maximizes the saw, you can expect problems and a labor intensive day. To keep your production in line try to keep your logs at 25-inches or less. To keep your customers happy with the big logs you will have to bite the bullet or charge a premium.
When confronted with rot, there is only one thing to do, that is to cut around it. This is what makes custom cutting on-site so interesting. The customer gets to see first hand what you are up against and you have the opportunity to provide him some education as to viable logs in the future. This type of job will make or break a custom sawyer. You must keep your cool, make it fun, teach the customer what is best and look forward to being asked back. If you learn to handle these situations, you will become an expert and a genius in his eyes.
** when cutting for myself, I shy away from the real large logs.