I just had the first case of a file not being copied correctly after using rsync that I noticed a few days ago. It was a raw image file so it was visually noticeable, some lines of pixels just went black. It may be unrelated, it may not have even been rsync's fault, but this drama and timing just makes me wonder if I got clauded there.
Do you not do the md5 or sha hashes of the copied zip file?