I suppose most of us use the one the insurer wants us to use and save money, I had trouble with that company, my daughter got a chipped "plugged" about 4 years ago and it started to open out a bit, unfortunately my insurer has moved to a similarish named windscreen company, so I needed to pay again as the insurer's terms had changed from "free chip repair" to "£25 if it is possible to repair" - when I approached the original windscreen company and asked for
help they said "sorry,we would repair it, but we have replaced our business management tool so we have dumped all our records" - I came back with "I'll send you a copy of the original work done sheet" - to which they replied - "these numbers would not mean anything to us now!" - nice work if you can get it, change business management tools every few years and walk away from trouble - now who lets them do that?
The biggest bit of that job - operating walking all round the car taking notes and measuring tyre tread depths - idiots?
Edit:- warning, taken off topic - sorry just had to do it!