DHL has the biggest footprint in China and Hong Kong.
The hub that they have at HK airport is truley massive when compared to all other carriers. I have used Air France Cargo in the past amongst others and found their service to be the same as most others, nothing special to be honest, gets in on time and provided your forwarder has customs clearance under control then you should be able to collect your goods from their shed quite quickly once its arrived.
Each carrier has their own advantages and disadvantages but it very much comes down to what kinds of goods you are shipping to where and in what kinds of quantities.
If you know how then you can make your airfreight imports are just as quick if not quicker than the express carriers just need to know what to ask for and how to ask for it!