It's not perfect. Nothing is. But it does make for a pretty informed decision. As long as you don't abuse it, there's always 2 hour refund policies as well. I don't think it makes the OP an asshole to pirate a game as a demo, but I've been burned so few times by this strategy that I've never considered some other means of trying out a game to be necessary. If you're really unsure, you can wait for a sale, too.