Devil May Cry 4 took me almost one week to complete. The main reason it took me so long is that Devil May Cry 4 was one of three games that I had waiting to be played while my Xbox 360 was in for repairs because of the red ring of death.
I also played Call of Duty 4 a heck of alot, too, which bumped the time up even more. all in all, I reckon it too me around 12 hours to go from mission one to completing the final mission. I had a blast playing it and I'm currently playing through on the...
... I love it!