I was always under the impression if the other party is at fault, they pay. That said.. there is a rediculous law which you are describing. I had a stone kicked into my windscreen off of a dumptruck driving down Salwa road. I ended up having to pay the 1500QAR deductible + 40% of a new windscreen from BMW. If you ask me, its ridiculous robbery. Whats the point of insurance if youre paying most of it out of pocket anyway? And the rates? 20% if your car is 1 year old? Most cars look showroom condition if they are looked after. Who is to say it requires "non-original" parts!?