1to1 copy of cod

[robo135]

i bought the game COD,and decided to make a backup.i tried the latest alcohol on the first disk.
it copied okay,so did the 2 disk okay.
i installed the game,but would not start with disks.
so i tried blindwrite with both disks,installed the game,and with the first disk in the cdwriter,i was able to enter the game and play it,no problem.
i checked for the protection,and it is safedisk 3.10,or something like that.
am wondering what the difference between alcohol and blindwrite is,as the alcohol is latest one i used?