The only slight snag with add-on Mesh, is that it sometimes conflicts with the
Altitude of some of the default (Mesh) Airfields.... ::)...!
They can sometimes appear on top of a Plateau, or down in a depression in the ground*...
...but apart from that, many add-on Meshes improves the accuracy of the landscape contours... :)...!
An improvement on the ground contours can be achieved by this alteration in the MAIN FS9.cfg file:
[TERRAIN]
TERRAIN_EXTENDED_TEXTURES=1
TERRAIN_TEXTURE_SIZE_EXP=8
TERRAIN_ERROR_FACTOR=98.000000
TERRAIN_MIN_DEM_AREA=10.000000
TERRAIN_MAX_DEM_AREA=100.000000
TERRAIN_MAX_VERTEX_LEVEL=19
Change to 20 or 21TERRAIN_AUTOGEN_DENSITY=5
TERRAIN_USE_GRADIENT_MAP=1
TERRAIN_DEFAULT_RADIUS=0.000000
TERRAIN_EXTENDED_RADIUS=0.000000
TERRAIN_EXTENDED_LEVELS=1307992
This will show river/stream banks more realistically (deeper)....;)...!
F....20 denier mesh stockings...nice!.... ::).....!
...and don't forget "VOZ Australis" for AMAZING various scenery effects and colours, and the beautiful "Koorbygen" buildings! (Works for the whole World...trust me!)...;)...:
http://vistaoz.org/* Example of conflict between Default Mesh, and add-on Mesh...Blake Sky Park CA57....>>>

...dig yourself out of that one!...

...!
Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.