I haven't heard much about the axis or mossberg models specifically but i i have been told by many gun enthusiast (don't just my shiz, i'm just repeating what i was told.) to stay away from the mossberg rifles, for various reasons but mainly cause they are cheaply produced (once again could be wrong i have never owned or shot one). Savage makes good guns, and so does remington. Altho i have heard a few supposed bad reviews about the 770, i would still swing that way, but honestly any of the 3 will work well for a new guy. Have him hold each one up and decide which one feels right.
Also look at the Ruger American.