There’s been two 10M Himalayan DEM’s for the sim doing the rounds for a while now. I’ve used both. I think Orbx one is of a wider area.
The 10M DEM is a definite improvement over the stock sim one but a higher resolution DEM is only half the story when it comes to good looking scenery. The other half is nice high resolution photo imagery to go with it. Sadly with the Himalayas the imagery coming off Bing is ok at best but most of it is fairly low resolution.
It would be nice to get the area looking as good as the Swiss alps but I’m not sure high resolution LIDAR scanning at that altitude is even possible? Maybe it is. Microsoft would need to invest in it.