lots of opinions, I shoot Ravin R10 light fast accurate that being said no need to spend 1300 to kill a deer.
I have owned probably 7 crossbows of various brands. Horton, Parker, Barnett( 2) Excaliber (2) , ravin (2)
I honestly can say any of them would be plenty to kill a deer at 30 yards and under.
I use the rail on my climber to steady. Like others said watch fingers make sure you get a crank for easy cocking and 4 hours practice he would be ready!
I have found some crossbows needed weight forward arrows ( bolts) to be accurate