It depends on against which countries you are comparing the UK/USA armies.
If you compare it with Sudan, Samalia, I am sure your 20 soldiers can win from 100 soldiers there, but against other SERIOUS countries like China, N.Korea, India, then man should not over-estimate himself too much, those troops especially Chinese troops are very hardly trained, if you think it is poorly trained, then you are or arrogant or ignorant.
Normal PLA training in Tibet:
http://img25.exs.cx/img25/9923/pla_land_031.jpg http://img25.exs.cx/img25/2624/pla_land_040_tibet.jpg http://img25.exs.cx/img25/398/pla_land_041_tibet.jpg http://img25.exs.cx/img25/9330/pla_land_042_tibet.jpg