U will definatly get great ratio of the same colour of your snakes. But there is a possiblity that u will get other morphs if both of your snakes are het for the same trait. there are 2 ways to find out what your snake is het for--- find hte breeder-- and get him to check the record and even then they sometimes are not 100% sure. And hte secound choice is to bred it and experiment.
ps---this post would probably be best suited in "The Cultivars (morphs)/Genetics Issues" part of the forum