Physics is as good as you know how to handle the physics object and your understanding of how actual physics works to apply them to your game mechanics.
Note that there are two stepping modes, dt, or framerate independent which is non-deterministic (may be bad for precision), and fixed, or framerate dependant, which is consistent but will run at different speeds at different refresh rates.
You should not be using other behaviors such as solid or bullet with physics. They will absolutely cause problems.
Often people end up realizing didn't need a full physics simulation to begin with for what they were trying to do, and would be better served by other behaviors and game logic/mechanics.