Chinese TV recently showed videos of Chinese commandos operating from submarines. This would be the equivalent of American SEAL commandos, and the first acknowledgement by China that they have such a force. This should not be surprising.
China has been putting a lot of effort into its commando forces, and not letting many details get out. However, based on what has been published in China, and what leaks out of the country via the Internet, the Chinese special operations forces (SOF) appears to be small, well equipped, and well trained. There are fewer than 5,000 troops in the Chinese SOF, organized into 6th Special Warfare Group, 8th Special Warfare Group, 12th Special Warfare Detachment and Naval Commando Unit. The 15th Airborne Corps is used as a major source of recruits. Thus Chinese soldiers know that if they want to become commandos, they have to get into an airborne unit first. The Chinese SEALs are apparently part of the naval commando unit, which has been seen operating from surface ships. Some have apparently been sent with ships serving on the anti-piracy patrol off Somalia. All this is quite recent.
At the time of the 1991 Gulf War, the Chinese only had a few hundred commando type troops, and they were intended mainly for long range recon missions. But after seeing what American SOF soldiers did in the Persian Gulf, the Chinese began forming units similar to American Rangers. By the time the 2001 war in Afghanistan came along, the Chinese decided to develop more commandos along the lines of American Special Forces, Delta Force, and British SAS.
Chinese SOF units mainly train and plan for operations against Taiwan. This would include attacks on key targets, as well as kidnapping or killing senior military and political leaders. Some of this would involve Chinese SOF operators who snuck on to the island as tourists or commercial travelers beforehand. China has been recruiting and training SOF personnel heavily for nearly two decades. That means they have hundreds of very experienced operators, each with over a decade of SOF experience. The Chinese SEALs are probably no exception.