AA Warranties - Worst ever

I had a policy with AA Warranties, the gearbox on my vehicle broke, they refused to pay saying it was wear and tear and not a breakage. I tried to argue the outcome, but it was a serious problem to even get to talk to them on the phone. The assessors report said he found a FULLY ASSEMBLED gearbox that he assessed. My question is how you assess a fully assembled gearbox. The report also said he did this in Kempton and the gearbox was actually in Mayfair. I asked for a second assessor to go out as a second opinion, but they wouldn't allow it. I won't recommend AA Warranties to anybody. Their sales line is always available but try to get through to their claims or complaints line. It is basically impossible.