My C4S comes in May and it's over Pounds75k so requires a tracker for insurance purposes. I assumed I would get a Tracker Monitor (about Pounds550 including fitting & 1st year subscription - as recommended by OPC when I ordered last year), but OPC have informed me that now they have their own VTS they won't fit any other trackers and any other trackers would invalidate the warranty. Theirs costs Pounds1300!!

Looking into this in a bit more detail, it seems that the Porsche VTS relies on 3 bits of technology: Smart Card, GPS Location Finder & Mobile Phone Communication

The way it works is that you have a "smart card" that you keep in your wallet. If the car is moved without the smart card being in close proximity, it alerts the monitoring station (using cell phone technology) and reports the car's current location (which it knows from it's GPS monitor). On the face of it, this seems all quite sensible, but as all of us know who use cell phones & sat nav, both technologies suffer if they don't get a clear signal. Sat nav is particularly sensitive, and will often loose access to satellites (and therefore not know where it is) when just driving in an area with a lot of trees. It seems that the minute the stolen car is hidden in a garage or a shipping container or just about anything that prevents it getting a clear view of the sky, the GPS & cell phone technology will be as much use as a chocolate fireguard.

Tracker systems (Monitor/Horizon/Echo) have a feature which means that they broadcast where they are on a radio frequency and all the UK police forces have cars equiped to home in on these transmissions. These are effective even in shipping containers/garages.

Tracker Echo, the top of the range product is still cheaper than the Porsche VTS and has ALL the features of VTS PLUS the radio frequency tracking. Horizon has all the features except the "smart card" and costs significantly less.

Advice or reccomendations from people on which I should choose based on other user experiences would be most welcome. Should I save money & get a better product but risk warranty issues or are all of them easy to defeat or is the VTS system fantastic or have I no idea what I'm talking about, etc.etc..