I tried Gleaming Insurance and they came in over double my renewal quote 
I got on the phone to my existing company and signed up for another year
Cheap does not mean it's a good deal.
With Gleaming they cover you for all sorts of cleaning, plus immediate family members are covered as well. That alone has saved me getting 3 individual insurances. Add to that the fact that they cover the glass being worked on, which most do not, it comes out as a very good policy.