I've done both in the past and for the moment, am rifle only. Bow hunting, I've found, takes a much deeper commitment and attention to detail than rifle hunting does. If you go through all the same steps scouting and preparing, patterning the game and picking your spots. Its simply easier to be 100+yds away, especially if you're stand hunting. Bigger margin of error in terms of concealment, making noise, having a comfy chair, being able to whisper to anyone hunting along side.

Thus, I think its considerably more likely to get a shot with a rifle than a bow. Bow hunting is a bigger challenege, in my opinion.