Everyone, the tracking company, the owner and the police are well aware of the need to trace before the bike (/ van) is broken or loaded.
Without the tracker I have a zero chance of recovery, with the tracker it's a 90% chance. That seems like reasonable odds to me.
The GPS tracker locates within a few feet and one of the service options is to receive an alert when the vehicle moves more than 500 yards from home.
I have not owned one before so I have no idea if they work well in practice. As I said before I shall report back.
I have had two scooters stolen, a Vespa was recovered three weeks later, a C1 that was never recovered and my daughter lost her first car (a cute Metro 1.3s) that was never recovered. We never claimed on any of these vehicles due to premium loading worries.
I'm not fan of alarms, I hate the idea of insurance companies wriggling out of claims on technicalities (such as alarm not armed etc) so I have chosen to go down the tracker route. Actually doing both is still cheaper than a topbox