as far as i've seen, and experienced, reloaders are working more time on the same batteries. Like i had a big tourney and had my realoader on for whole two days, and turned it off only at the end of the games every day and it worked fine. Though have seen some Halos freak out and start eating batteries like an irishman drinks beer after being sober for a year.
Also on the realoader you can adjust speed, which is sorta cool
Disadvantage with the reloader is the fact that sometimes it takes another noise as a shot - filling a pod, dive, slide and stuff like that... my reloader haven't done any probs yet, and not a single reloader i've seen. But halos did....