Anyway nice pic there.
The frist Hong Kong police pic post:
The 2nd and last pic are PTU unit,
the 2nd last is Airport Security Unit.
An SDU like unit responsible for providing the initial response to any terrorist incident at Chek Lap Kok International Airport and to respond to other security threats and emergency situations at the airport.
1st and 3rd are regualer police.
The 2nd Post.
1st traffic police.
2nd PTU.
3rd EU unit
last 2 are regular.
Read this it prove that SDU trained with US Navy Seal
Here some nice SDU pic I got of the police website during lunch.
IMO it fair to compare the SDU to a company size special force military force in the CT and domestic emergency respond, especially in Urban operation and CQB.
As most SDU has a doctrine which cover a much wider role the standardize Swat style unit and is mostly head into the military role.
For example CT, the compability to launch an assault from land sea and air, and under certain situation the extermination of certain target which is a threat to national security (this is actually in there doctrine which is strange for a police unit, unless it has to handle the national security role which is normally handle by military unit).