Yah, we retrofitted our place with the solid doors. With the heavy oak door, it came with pretty beefy hinges, but as noted, you need to make sure you are using extra long screws screw securely into the frame.

That said, you also have to be realistic about how effective those long screws are. Even with the fairly beefy door and long screws, someone can beat their way through -- the screws will get pulled out of the softer wood used for framing, or will simply break out.

But someone is going to have to come with appropriate tools and make some noise and work for it.

-john