Same as the other reviews; their business model appears to be to charge you for the installation fee of the black box and then calibrate it to ensure no one can reasonably drive within their parameters before cancelling your policy and charging you 45 pounds for cancellation and 90 pounds for the removal of the box. I called when my score started to drop and asked about the algorithms they use to meter your acceleration, braking etc and they were less than useless; as a mathematician I still can't figure out any sensible system this could be based on! Apart from losing bucket loads of money you'll just end up stressed the entire time you're driving, not to mention accelerating and breaking so slowly you end up putting yourself and others at risk.