Just from watching that video and the other videos on the 'YouTube' link I would say from personal experience it is a little more diffcult than Aspen Colorado (KASE), but that much more diffcult.
However, I've never landed at Paro Bhutan, so I cannot really tell for sure. I have operated in and out of Aspen close to a thousand times.
Because of the weather conditions the Falcon 900 video was impressive, but with my experience in flying Falcon 900s there was no period on that approach that you could not safely abandond the approach and scucessfully climb out of the valleys, even with one engine inop.
As p51guy posted TGU is as about as diffcult, I flew 727s in and out of TGU.
Sadly now that I am retired I'll never have the chance to fly an aircraft into Paro Bhutan.
Nice videos.