Are they any good? I know that if someone wants the van they are probably going to get it no matter what is on it. We alreay have an alarm and alko hitch lock which satisfies our insurance. We have widened the wall for easier access for the van and this has meant we have no gates short term. Hence wanted a bit more security but nothing too big and heavy or pricey? We were thinking of the SAS clamp which looks small and light (around £50) or I have seen that Milenco do a light version (£30)of their version. Any thoughts?