Bro I am also in pursuit of this issue BUT from my experiance, The PSO pump at SMCHS is awesome (Its on Shahrah Faisal, It will be first pump on your left if your are from metropole to airport).
PSO pump near Creek Avenue is aweful, a big CHOR,
The Shell pump which comes after Caltex's at karsaz is also ok. If you get to know any more then let me know