I specialize in Fl/Brooksi Kings (and I’ve not kept the other colubrids mentioned) so my input is very biased lol 
They definitely are a wild tempered snake to work with, though they aren’t necessarily mean or defensive. They have an insanely good feed response and will mistake non food items as food, its happened to me a ton in the 12 or so years I’ve worked with them.
The good news is that you’ll most likely never have to waste a meal with them and you’ll never struggle with picky eaters.
Now another thing is, for how wild they act they actually tame down much easier than other “wild” species I’ve worked with. Once they get handleable to a point they know you are not food they are great to handle, they are very active and curious- so if thats your cup of tea then they’d made a great pet.
You just might need to have a snake hook handy to let them know you aren’t food when you take them out. 
Edit: I guess I should talk about their care as well 
got too sidetracked in how their behavior is.
They are very easy to care for, they need a bit higher humidity than other Kings that I’ve noticed. I keep mine at about 65% ambient and 70-75% in humid hides, keep in mind their native range is in the Florida everglades.
Temperature range is the same as Ball Pythons to make it simple. About 72-75°F for cool side, 84-86°F for warm side and no higher than 90°F for basking. They like basking too, I often find mine laying on their basking areas at morning-noon.
They are diurnal, so feeding is reccomended more during daylight hours (mine eat just as well at night but I like to keep it closer to their most active part of the day).
And they will eat just about anything that is safe for them. I like to give mine mice, sometimes quail chicks and chicken organs… its a hit or miss but my late female absolutely loved hard boiled egg as a treat. I feed babies every 5 days, juveniles once a week and sub-adult/adults every 10-14 days.
You’ll need to offer deep substrate that can hold its shape somewhat, they like to burrow too.
