Totally agree Jarvi! There should be a thread spreading good experiences re car hire.
We tend to use Dickmanns. I know the reviews are rubbish - but no other companies fare any better.
We have never had any trouble with them ( used them 8 times in the last 3 years approx) but, regarding the reviews we have put the lack of problems down to good luck.
However, in May we hired a car and when we returned it we were told we would get a refund on the petrol in the tank. 'Oh yeah !?!??' we thought!. We never expected it and would not have used the energy fighting for it . BUT a refund was in our bank within a week. Can't remember the numbers involved - just gobsmacked we got anything.