Traveled BA F; EK F; CX F, the past week and following are my observations:

SEAT: all are quite comfortable; Prefer CX for its no-bling suite; Prefer BA's colors; Prefer EK's bar

LOUNGE: EK's DXB is notch above CX's HKG but any day prefer CX's more comfortable shower room!

IFE: EK has an edge over CX and CX has an edge over BA

SERVICE: all were good w/subtle cultural differences

FOOD: all were good; BA's beef, EK's lamb, CX's Chinese...

AMBIANCE: CX has an edge over EK (EK felt little claustrophobic) and BA felt bit like business class cabin

If all there were on the same route and there is big fare difference I will go for the lower fare one. If all there were on the same route and there is negligible fare difference I will go for CX

2 cents....