PRV V6 Volvos - are they really that bad?

I agree the PRV engine was a joint design with Peugeot and Renault and I don't understand why the Volvo version seemed to fare worse than the others. I suspect Volvo tried to tweak some of the details which made the engine less rather than more reliable: for example the camshaft lubrication. I had a B28E engine in mine (fuel injected) and it mostly went like a bat out of he'll. However only a few weeks after a service and oil change it developed a camshaft rattle that was worrying. When I sought advice the Volvo agent was determined to charge me £3000+ to re build the engine and reused to discuss any other possibilities. It wasn't possible for them or me to agree the job immediately and so I had to drive with the rattle. About a year later I rechecked the cams and found a few valve rockers badly worn and the cams were fine. That cost me £120 to fix. In doing this I also found the oil holes in the new rockers completely bunged up with preservative that had to be carefully cleared with a fine drill bit. Volvo agents were also dishonest to me about keeping idling speed reliable. Only 3 months after I bought the car as Volvo approved used, they tried to say it was my fault that because I hadn't had the car serviced in that 3 months it was my fault the car refused to start. It turned out that all tat was needed was to remove the W shaped inlet manifold section and wiping clean the throttle buttflies occasionally. The other pain on that car was rusting exhaust pipes where the two branches came together, only ever last 5 years at best with official parts. Finally I know the PRV engine had a rotten reputation for over heating even on later versions as used in the DeLorean sports car