Pretty extreme!
There is a mountain airport in France - can't recall the name, but the runway is severely sloped, you land going up, take off going down...and there is a 1500 foot cliff at the end...it's even more extreme than this one, but no passenger jets, only turboprops.
St. Maarten is just cool...not extreme, really, lots of airports have similar terrain challenges to St. Maarten...but watching teh Air France 747 land from the tiki bar by the end of the runway with a mai-tai in your hand? Cool...and the tourists who don't know about the runway? make me wince when they get blown over...