Question about Terrain Editor

Hello, I am a new member and I have a few questions about the TGEA Atlas Terrain editor. I searched and found out about Dekker Ying's Plugin and I was wondering if the official editor allows user to combine meshes into a limitless, detailed terrain(I believe this is known as paging). I also looked at L3DT in the addons section and was wondering if it could do the same as Ying's solution. Any help would be greatly appreciated. I'm trying to make a huge open world game with a detailed enviroment and I was wondering if I could combine worlds and terrains to do it.