Take it one by one.
I know the SF videos etc. can look really cool but remember that the amount of work that goes into one of those "cool" scenes is really monumental. The part where the guys are bad ass on those Zodiac boats with the rifles at the ready infiltrating a sea side cliff... that's the EASIEST PART. They don't show all the drills, repeats, PT, memorizing, more drills, do-it-all-over-again, cliff climbing, packing, unpacking, packing, unpacking, packing, unpacking, wind chill while wet with sea water, wishing you ate more, wishing you ate less... I remember being on the back of one of those things struggling to stay awake. Yes the sea water is freezing cold, the air is rushing at you and your eyelids feel heavy. And I wasn't even SF or Recon.