I've tried the new X-Plane and it's not great. In a few years no doubt but FSX has many years ahead of it yet, people are onluy now beginning to reach its potential. See these addons...You can make FSX an incredible experience..
Active Sky 2012
Ground Environment X
Ultimate Terrain X
Real Environment X
Ultimate Traffic 2
A few UK2000/Flytampa/Aerosoft airports
And of course, the king of fsx...
PMDG Boeing 737..
There is no comparison on the commercial market - it's expensive, but you cannot beat it.
To put it into perspective, the NGX comes with about 6500 pages of manual...Sound professional enough? :)