When I bought the house the garage came with an up-and-over with a couple of decent locks at the bottom. Then some scrote decided to try and get in a couple of years ago – tell-tale marks around the centre of the door at the top where they’d tried to pop the lock…
I’ve since run a chain (inside) about 15cm down from the top of the door, running horizontally from an eyelet bolt on one side, through a couple of rings I’ve fixed to the door on each side, through another eyelet on the other side, then padlocked to itself. The eyelets are siliconed into the garage wall. It’s not ideal, but will stop anyone simply bending the top of the door if they’ve managed to pop the top catch. The chain runs close enough to the door that you can’t use a bolt cropper on it from the outside.
I did consider batons, but the door’s set into a concrete frame and there’s no way to use them. They would be more convenient than my solution, although the chain’s pretty easy to remove.
Edit: the chain’s pretty noisy in use, not sure how much of a consideration that is to you.