My worse flight was with KLM from Karachi to Amsterdam. I had a bad case of food poisoning before I got on the plane. It was a horrific flight where the staff with the exception of one stewardess were horrible. I have since that day always avoided flying KLM. Of course over the years I have had other bad flights with Easyjet, BA, Air New Zealand and Delta airlines. After flying from Miami to Peru with Delta I swore never to fly on an American airline again and have managed to do that so far. The tray table literally fell to bits and the seats were like something you would find in a wreck at a car junkyard. I wondered if they maintain the interior like this what must their engine maintenance be like! To cap it off an American gospel group started singing hymns. I really felt very happy to be back on terra firma after that flight.