Yes the lock is expensive, but you are more likely to lose your trailer if you use a cheaper lock. I have many different coupler locks and this one is the best. If you do not have insurance on your trailer, this is the way to go.
After a lot of research and using inferior locks, I settled with Altor, and I couldn't be happier. The quality is unmatched.
Exactly what you would expect, a lock that's not going anywhere without the key.