I went down a rabbit hole a few weeks ago in regards to the HD/UHD Mesh from AI pilot and Forkboy ortho. The consensus I gathered is that A) Ortho doesn’t use the mesh from AI pilot X because its already embedded in the tile and B) The Ortho4xp/Forkboy mesh is better data than HD v4 mesh. The mountains still look great, I got the Grand Canyon HD Forkboy and its awesome.
I keep the AI pilot mesh for areas that aren’t covered by Ortho.
Two mods I highly recommend if you are using Ortho:
Transparent Autogen Terrain. Basically it removes that little square below all the autogen houses, and makes the houses look 1000 better matched to the ortho. No negatives to this one.
Transparent Roads. Same thing for roads. Removes the roads and just has light posts, traffic lights, and cars on the ortho roads. Keeps the stock highways and bridges. This one is up to you, personally, I like it alot better than the stock roads, but if you fly over an area with no ortho, the roads will be transparent with no ortho road beneath it.