If both answers equally help, and solve the problem, then judge them on how they are written and structured and how much information they give. That's what I do, and I've never had a time when answers are so amazing that I can't even judge them on that.

You shouldn't accept neither of them though because you need in some way to mark the question as solved for other users and the system. Because then other users may not even realise that both answers solved your problem.