At least with our current understanding of causality and consequences there no real fundament to choose one type of morality over other. In other words, you can't argue that utilitarianism will be better than deontological ethics because you will never know the real outcome of an action in the real world. There are just too many variables.
As for ontological, you can't be sure that is "good" or "bad" with 100% certainty. Kant will say that good is everything that if everyone does the same thing then you will be ok. That's a lot to speculate.
Imagine for a second that you got the chance to kill Hitler before the Holocaust then an even worse genocide occurs.
The world is a chaotic system, one little change can produce a totally different output. So, after all, you shouldn't mind what you did or what happened to you.
But with that in mind, I built my own rules of morality and I feel really good with that.