I started the first Asiatic campaign yesterday. Right now I'm headed to the South China Sea for the third primary mission with 45K tons after a toprp refit....damned duds. Saved file is about 2.3MB with 1.3 and no mods and no .cfg change.
My impressions are the game loads faster, saves about the same, and seems fine in thos respects. Oh yeah, the torp doors are on steroids and the new boat (Salmon) seems to dive faster than a lead brick..