Locks that work

Added the Artago lock to the list, as recommended by Pragma. It seems very superior, but more pricey than I'd expect, for an unknown brand (in the UK). Nearly £120 is a lot of money. Its Sold Secure Gold for Motorcycles, so its good enough for us.

It is a good lock, but beware that Artago seem to have a funny idea about how to quote their dimensions. We have one of their 320mm long D-locks here and it is actually about 320mm from part of the lock body to the top of the shackle, so the normal, inside, measurement is actually closer to 295mm. They quote the 85mm internal width and that is correct. I imagine the 270mm model is actually closer to 245x85mm internally, although I can't confirm that as we haven't got one here.

These are also heavy: the 320mm one is 2.73kg.

Good locks with 18mm thick shackles, and the unusual sizing might actually help in some situations. Expensive, though (and keyed-alike is not practical at all).