Burms are great, my buddy has an albino female. But there's a few negatives to consider:
1) The cost of feeder rabbits (aren't cheap)
2) The size of the poo....like a dog or larger
3) The size of the snake (obviously)
4) Temperament isn't terrible but they ARE aggressive around feeding time. Just keep a hook handy to let them know you're not food. That being said, every snake is different. Some are MAJOR puppy dogs and others are rather pissy. You don't want to get bit by an adult. I have, and it cost me a trip to the hospital and 13 stitches. Not fun.
...as said before they are great animals, but just keep in mind that they have SPECIFIC needs that need to be met and like any snake they live a long, long time. I can't say that I would personally, jump from a ball python to a burmese. Maybe consider a boa.