A word on insurance. It is not uncommon for insurance policies to state the kind of lock to be used in order for the insurance to be valid. You *need* to check the small print. If you aren't using an 'approved' lock then you may well find that the insurance is invalidated just at the point when you are making a claim. You may often find that if a specific lock is not named, a specific *type* of lock is. For example, a cable lock may well not be valid, but a D-lock is. It's also common for it to be stated as to what a bike can be locked to in order for the insurance to be valid, with the phrase 'immoveable object' being a common one in use. They key is check the small print - phone up the insurance company and check - better to be safe than sorry.