I fitted the Laser Interceptor in the July ($450) + shipping from the States & use them in conjunction with a Valentine 1.
I have found them very helpful on at least two occasions since, one at 75 on the M6 toll and a second time with a mobile unit in North Wales.
The process is pretty straight forward. The tricky bit is ensuring the laser heads are level on both axis.
Part of the system is a small control unit from where you can plug in a PC for any updates, and the voice warning is emitted from. Importantly, you must be able to switch of the sensor heads either manually (I have a switch on the dash) or automatically, you can pre-set so after sensor is activated it will switch of after say 10 seconds allowing the correct speed to be obtained and not continue to JTG (Jam to Gun) which old bill do not like!
It works as a good parking sensor to, or turning the lights on in my house as I turn in the drive.
I have to say that without it I would now feel very exposed.
Hope this helps you make an informed decision.
http://www.guysoflidar.com/july-2008/la ... -test.html
Very comprehensive testing site for laser jammers
http://www.laser-interceptoruk.com/index2.html
Laser interceptor site.
Cheers
Roger