One other downside to garage openers -- they come with an emergency cord that lets you open the door in the event of a power failure.
The problem is, you can wedge the top of the door open a bit, and slip a wire hook through there. You then snag the cord, and with a sharp tug you're in.
The padlock on the rail is the only way to prevent this, but the problem is that you just negated why you bought the opener in the first place - the convenience of being able to hit the button in your car and not have to get out in the rain to lift the door open.
Chip H.