Avastar-1.2 fully supports Fitted Mesh and has a bunch of improvements regarding the user interface. Avastar-1.2 has been tested on Blender 2.70 . It can run on newer Blender versions. It should run on Blender versions down to 2.66 but this has not been tested.
This version supports Liquid mesh. It provides the Collision Volumes and it allows to weight the bones and export them. So Avastar-1.0 is technically able to create fitted mesh as well. However, it does not support the PEC bones, the BACK bones, the HANDLES and the BUTT.
Note: Avastars-1.0 does not run on Blender 2.70 and newer and it does not provide full slider support.