vocals to a bus?

i currently do not record with any effects on, but once everything is laid out, i usually send all my vocals to a bus thatll have my main effects for cleanup ect...im wondering...while using a cpu heavy plugin...specifically AUTOTUNE PRO, alot of my clients like to use it in real time, which isnt much of an issue. but im curious how some of u would handle this....would you put autotune on a bus and send the  tracks that need it in real time to that bus ? or put it on each track manually?