His attempt on Micah's life was more successful.
On a more serious note, in my view, Arthur has a lot more going for him than John does: he's more intelligent, stronger and more amicable with people. Yet, John is a lot luckier than Arthur is. Despite Arthur possessing qualities that John might wish he had, it actually ends up being the other way round, in a way, as John has the opportunity to live the life Arthur wanted.
They are quite opposite: Arthur had a lot of natural talent and potential for various things but he never had the chance to do much with them and, ultimately, you could say, his life was a tragic waste. John, on the other hand, didn't have so much going for him naturally, yet bettered himself when presented with the chance Arthur never had.
