It is NEVER wise to confine two pythons together in the same enclosure (except for breeding) unless it's in an aviary with lots of space, and you'll run an even greater risk with one being almost double the size of the other. Things may go smoothly for an indeterminate period of time, then one day you'll come home to a bloodbath, and one or two dead snakes.
Of course you'll get a few people saying they do it without trouble, but it's usually only a matter of (sometimes a long) time.
Jamie