I agree with everyone else; but don't be fooled, kings can and will inflict a nasty bite if they sense "food" on your fingers/hand or are biting out of self-defense, and they hang on with some tenacity too; they have very powerful jaws and a large king can put some slices on you.
Having said that, they are usually very docile snakes, even wild caught ones. As far as parasites, I agree too that they should be wormed...I worm my captives (whether wild caught or captive bred) because kings naturally tend to develop a gut load.
My very first king was a crisp, white and black Cali and it was a great snake. But I disagree that they are the more aggressive of kings: speckled kings, deserts, and Florida kings tend to be very agressive when smaller and I bet 75% of my bites still come from Florida kings - I always found the Cals I had to be the tamest...but then again I've never caught one in the wild.
Either way, just make sure you know how to care for your wild caught pet if you decide to go for it.
And I agree again with the others, the natural variation in kings is amazing and quite beautiful, and I prefer to have wc myself.
Good luck!
-John