I leave mine hanging on the wall. But I also try to shoot at least 3 or 4 days a week so hanging it up makes it easier to access.

I would say that leaving in the case would cause some parts to rust a little faster. Same thing happens if you leave a gun in a padded case for an extended period of time.

So take it out & shoot it a little more often & you can worry more about wearing the paint off around the grip than having parts rusting up.