Best - CCR
Worst - TLV - that tiny little 'private room' is cramped and always very crowded before the BA flight. Food is in the regular business lounge and the booze is the same. The service aspect is a joke - one poor girl trying to handle all the DYKWIA types in the lounge.
Honoury mention goes to NRT - Its not a bad lounge (Continental I think) but in a station like NRT with up to 2 747's a day, there is absolutely no excuse not to have an F lounge.