Well it depends. First off i'd say milksnake. I just like them better. Here are some big differences between the two. I'm going to add in the ratsnake in comparison (thats always been my favorite)
Attitude in the cage -
Python - Lays around, very lazy. Rarely moves or whatnot.
Milk - grows to be somewhat active, however not as much as a ratsnake.
Rat/Corn - very active throughout life, loves to climb.
Attitude when being handled -
Python - very docile. Usually non agressive. Once they get used to you, they will lie around your neck or whatnot.
Milk - Keep ahold of this snake as a baby, will try everything to get away from you. Calms down as an adult, but still active (interesting to me).
Corn/Rat - I have one rat who is the most docile thing who just lies around on my arm and doesnt do much, I have some that tried to run out of my hands until they got used to me and now they just crawl around my arms and whatnot.
Housing -
For all snakes its reccomended to house them seperately.
Python - hoenstly dont know if they are cannalistic or not.
Milk - will eat other snakes, can even kill those larger than it easily. (they are a subspecies of kingsnakes)
Corn/Rat - can have some cannibalistic tendencies as babies, however i've never had a problem.
Feeding -
Python - Get ready to feed large mice, maybe even baby bunnies if they grow large enough (I know burmese will eat a rabbit a week, unsure about balls)
Milk - lizards, other snakes, rats, mice
Rat/Corn - rats and mice
If you had to choose between those two, i'd go with a milksnake. However I love ratsnakes. But I also really enjoy having a very active snake..I don't want something that's going to lie around in the bottom of the cage and do nothing all day and all night, like a python will. Also be prepared to get a fairly large house for the python.
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The reason mainstream thought is thought of as a stream is because it's so shallow. -George Carlin
Battling ignorance one stupid person at a time.
Current snakes:
0.1 Licorice Stick Black Rat(Lola)
1.0 Neonate Black Rat (het for Lic Stk's) (Frankie)
1.1 Texas Bairds ("Bill" and "The Bride aka Beatrix Kiddo"