As stated in the release notes, there is no ingame download.
I had the exact same MB numbers on steam as you had and offcourse no ingame data to download.
For me it reduced the very long ingame freees (>20sec), but there are still minor stutters (now a bit more irritating since they now also let the sound stutter).
So for me there was an improvement.
Blurred and unsharp textures in the distant unfortunatly still exist (although I have the terrain LOD on 5)