...you have 3 options. Wait for it air on TV, rent it, or borrow it from someone.
Borrowing it from someone is illegal too...no different than downloading it, you're still seeing something you didn't pay for.
I too have tried before I buy and most definitely delete the entire thing if I am not interested in it. You have to hold yourself to that standard though, but that's not saying everyone does.
Wait, so I asked my friend if I could borrow Casino Royale and he said yes, but I still did an illegal thing? That's probably the funniest thing I've read today.
What was I supposed to do, give him 5 bucks to "rent" the movie? Back in the 90s, borrowing wasn't actually frowned upon.