For PunkerSXDX: The only Mh-53's are the Sea Dragon, "E" model, used by the USN as a flying mine sweeper; And the Pave Low III, "J" model flown by AFSOC in support of US SOCOM missions. The USMC ( Uncle Sam's Misguided Children ) ride the CH-53E Sea Stallion, which they use primarily as a heavy lift chopper, used to carry artillery pieces and lightly armored vehicles into forward positions.
The Pave Low III is considered to be the most complex and advanced helo in the world. They are used only for the most intense and secretive air insertions deep in enemy territory. Indeed, a pair of MH-53J's led a flight of Apaches on the first attack of Desert Storm to clear a path for the Strike Eagles to go "Down town" into Bagdad. Were it not for the Pave Low's strike mission, the Iraqi's would have had about twenty-five-thirty minutes notice that the first wave of Eagles were inbound. As it was, the Iraqi command structure was taken completely by surprise, and was totally devastated from the very beginning. They of course, never recovered from the initial attack.
And Mr.ThunderMakeR: Sorry mate, we Air Force brats refer to the MH-53, as the "Pave Low". I thought you meant the Sea Stallion. My bad.