I wound up going to a reptile expo and falling in love with a yellow belly for my first (and only so far) ball python. He cost me about $120, which is about what most of the male mojaves ran give or take $20. I have had 0 problems from him, save for a 1 month off feed spell, and if I want to breed him in the future, I can pick up another yellow belly for a possible ivory. I have read that spiders have a higher probability for some unusual personality and behavioral quirks, but have no personal experience to back that up. Ultimately, it comes down to what you like and how much you are willing to invest. Balls can live for over 20 years, so don't get something that you don't want to deal with in the long term.