Unfortunately, I think if someone has the intention of stealing your material, they'll find a way to do it. There's always "a way" for anything. I used Adobe Acrobat to write my best-selling ebook, and I intend to use it again for my upcoming works. There's always people who steal, so you shouldn't be too worried about it. What's "mac binding"? Never heard of it. I protect my Adobe PDF with a password so that only people who buy it through me can open it. But I know that can be hacked, and it doesn't worry me. The best thing you can do is file for official copyright of your work with the US Copyright Office, so if anyone messes with your work, you can sue them. You can also do a poor-man's copyright, which involves mailing yourself a copy of your work so that it has a seal on it, and this may hold up in court. The Official US Copyright is less than $100, and having used it before myself, I think it's well worth it. A while back someone on eBay was selling my ebook, and I easily got them kicked off and prevented what they were doing. Good luck.