I have been on both. Geodon made me gain a ton of weight, made me a zombie, and gave me very bad tremors. I had several other side effects and ended up taking 11 pills a day because the side effects had side effects. I don't remember much about Abilify. I wasn't on it for very long, so I guess the psychiatrist decided it didn't work for me. But a lot of people have positive things to say about it, and I didn't experience any side effects while on it.
So with that in mind, just go with trial and error. Geodon might work really well for you. But I want you to be aware of potential side effects like tremors, vertigo, weight gain, constipation or diarrhea...It did something else, but I can't remember what. I was so over medicated I barely recall that period in time, but I know the psychiatrist put me on a pill to counter a side effect. Sorry I can't remember.