There is a person who posts on the Casio board over at dpreview who has dropped his Z750 several times and it still works fine. He says it has a couple of decent sized dents. Several others chimed in with drops that didn't disable the camera. I've dropped mine in its case a couple of times on hard surfaces and it is still functioning. I've had mine since it was first released with no problems so far.
If the lens was extended and it landed on the lens just right I suppose any camera could get jammed. It seems to be a reasonably sturdy camera now that they have the lens error problems solved. If something happened to mine and it was unrepairable I probably like it enough to replace it. But I would really feel dumb if the second one broke.