I've passed them up for quite some time because of the same reasons. Wouldn't feel right cutting em. It's real tough to find a straight piece but I'm sure there around. Dennis, I'm down in Naples and we've got a lot more swamp/scrub oak down here. I have a hard time getting my hands on that stuff because they're either too young or too twisty.
Not sure if you're just getting started with this but if you haven't given Australian Pine a try yet don't pass it up! It's invasive, easy to find, seasons fast, grows straight, and can have a specific gravity over 1.0.