I flew from UK to Thailand by Qatar Airways, my family which consists of two adults and two small children were slightly overweight on baggage, a total of 10 kg, 2.5 each; yet we were charged 433 UK pounds. I have flown many times, with many airlines and never been charged for such a small weight. In addition, seats were dirty on tyhe flight from UK, probably as the ground staff are too expensive, so most cleaning done in Doha.
I would not recommend Qatar Airways.
Fly by EMIRATES, they are fantastic and have a 30kg allowance.