Actually, Air Force Special Operations Command uses the MH-53J/M Pave Low a great deal, for combat search and rescue, for covert insertion/extraction and resupply. Training is with the 58th Special Operations Wing at Kirtland Air Force, N.M.; many AFSOC units are based at Hurlburt Field, Fla.
Owing to their advanced sensor package, Pave Lows led the first Apaches into Iraq in Desert Storm.
MH-53s took part in the extraction of the downed F-117 and F-16 pilots in Kosovo. That is not to say they are without fault. They are big and expensive to maintain.
Other H-53 variants have more traditional heavy hauling uses, particularly the CH-53 Sea Stallion.
For a fictional account of the MH-53 in action, I'd refer you to Clancy's Clear and Present Danger.
John Pike's fine site:
http://www.globalsecurity.org/military/systems/aircraft/mh-53j.htmchrs, jl