This game just came out yesterday and I downloaded it. It is 40GB and it took me about 20 hours to download it. (My download speed is between 4 and 6 mbps)
So I played through what I guess is a prologue and then the first scene of the main character coming home. Already had two driving episodes so it will probably be filled with driving which is probably my weakest area in these games.
The graphics are great and the acting is great as well. The combat is pretty similar to Mafia III.
This game is about a character coming home from Vietnam while Mafia II was after WWII. The character in Mafia II was depicted as probably Italian American, while the Character in Mafia III is African American.
I'll probably have more comments after I get further into the game but I don't know how soon that will be as I am in the middle of Two Worlds II and just started Mafia III to have a look at it. I don't know I may abandon TWII and dive into Mafia III.