Just checked my history on Trips. 400 sectors on staff travel. Downgraded? 4 times. Offloaded? Once. Best stations? In order of memory: BKK, HAM, FRA, ZRH, BOS, KUL, SIN, PRG. Bad stations: MUC, CDG, TUN, SYD, MEL, NBO. Worst station of all times ever: AKL.
Runner up: Still AKL.
Never had an issue with the colleagues on board ever. Quite the opposite.