Terrain Importer Features
Import Tile Sets of (theoretically) any size
By creating terrain prefabs out of your import files rather than generating the terrains in the scene (though both options are available, and can be used simultaneously), Unity's editor memory limitation can be circumvented.
Import one more more RGBA Splat Maps
The import settings for the splats are automatically configured prior to being applied to the generated Terrain. Any image format that can be converted by Unity to a Texture2D should be supported.
Import Height Maps under a variety of supported extensions
.raw, .r16, .r32, .ter, .tif/.tiff formats are all supported. Additional height map extensions may be added in the future.
Import Settings are stored as Scriptable Object Assets
This allows for quick and easy re-importation. You can also create a base file which stores common import settings (such as the location where you import files are located on your machine), and then duplicate this file to generate new import settings that require less configuration.
Generate Prefabs for your terrains automatically.
The tool takes care of everything.
Configure the Terrain Settings for all imported terrains
This is incredibly useful when importing tile sets (imagine having to change the Pixel Error/Detail Distance/Tree Distance/etc. for every terrain in the tile set after import!).