The alternative, of course, is the French stuff that's coated with porcelain, which eliminates the nutritional benefit of cooking with cast iron.
I use cast extensively in our reenactments and the many vouz's that my family attends. You've gotten good advice except for one thing... and a couple of observations.. I use Lodge exclusively and have over 150lbs of cast I carry around (I know, I know but it looks good!) and if you inspect it before buying to look for roughness, I've never had a problem with any of it.
Cleaning with salt and towels works good, boiling a little water in the pan also works very well for sticky/stuck stuff, but NEVER use soap or scratchers or you'll regret it.
Seasoning is best done with animal fat, I use unsalted lard and I can cook sausage gravy in my dutch and then wipe it out with some towels when done and it is clean and ready to use again. To make sure the outside doesn't rust I get the cast to hot to hold with bare hands and then use a beeswax candle and coat the outside and wipe it in with a towel. Will NOT rust, and once you do it a couple of times it never needs done again..