I have only killed a rabbit with a 44 magnum. I have taken up to mule deer with a 357 magnum so I am sure that the 44 would be fine on the deer as well.
Shot placement is everything! I would rather take a round of 50BMG to the foot than a 22short to the base of the skull.
all 25 of my guns are 45/70 govt, 357 mag, 22 or 12 ga... I believe in keeping it simple