After they botched my dog's trip from Chicago to Hong Kong, I will never fly KLM again.
As there were no direct flights (then) from Chicago to Hong Kong, and thinking of my puppy's bladder, we decided to transfer in Europe to break the trip half way. KLM's animal hotel was then rated top notch. All went well until I stepped off the plane at Kai Tek to collect my doglet. "Umm...err... Mrs MC, there seems to be a slight problem..." The pilot from the first leg forgot to hand over my dog's travel papers to the pilot on the second leg - and without those papers my dog could not enter Hong Kong. To make matters worse, the first pilot , still in possession of my dog's papers, was now on his way to Tel Aviv. So they had left my dog in Amsterdam - and this was after they had assured me she was on the plane. There I was in HK, my dog was stuck in Amsterdam, and her papers were somewhere in the skies over the Mideast.
(The scene that followed was not pretty.)
OK - this was 17 years ago, but I still can't forgive them.
I loved the old Swissair and it's hard not to compare Swiss unfavorably to their predecessor. So I try to adjust my expectations downward and give them a break, assuming they manage to get me where I want to go more or less on time. I do have one persistent gripe though... must the cabin personnel be so patronizing when correcting my German grammar?
The only truly pleasant flights I've had in the last few years were on Singapore, Cathay, and Emirates.