At $100 I wouldn't expect much deterrence in a safe. This isn't fireproof, waterproof and the outer layer is fairly thin it could be punctured with force. What this safe brings is overall volume, weight and the ability to be mounted. I don't have this mounted yet as I don't have a permanent place to secure it, but where it is now I think I'll secure it to the wall once I'm happy. It weighs pretty hefty without anything. With at least 10-20lbs of items a thief may have difficulty walking out with it. It has no ridges that it if not held from the bottom it can slip off your grip.
I have a 15" x 11" fireproof document holder and it's a tad too long. What I can do is fold the extra space and place it on the very bottom. The shelf can be easily knocked up and over if you don't have anything placed on it with weight. Volume wise it was way bigger than I needed it to be. That's fine as I can add more things of value. It's hidden from plain site and I have it covered with furniture and objects that It provides some kind of deterrence while getting into with easy access.