Some answers.
If you bang your watch on a wall, it is evident that you may damage it.
It is not adviced to practice sports with your watch, with any mechanical watch, by the way. Think about it, when you play tennis, or golf, the rotor and the delicate parts of the movement will be in danger at the moment you hit the ball...
But you can swim and dive with it without any fear, of course.
The Cal 1315 is a very good movement, but a Rolex would be more accurate.
As for the resale value, it should not be your most important criteria. It is less easy to resale than a Rolex Submariner, for example.
Buy it because you love it, not because it will keep its value.
Best,
Nicolas
This message has been edited by amanico on 2012-11-02 15:14:20