Need thoughts on battery operated sawsall

i second that on both the milwaukee hackzaw and sawzall,,,i own a construction company, and we have used them all,,but those Milwaukee cut circles (no pun intended) around the dewalts and craftsmen models we have used. we can cut for an hour on a milwaukee battery and man, talk about torque! hands down milwaukee for us,,,
Wow an hour on a battery!!! Goly crap thats great!! Was it a lithium ion battery?
I would imagine they have a longer life on a charge cutting thru thin gage sheetmetal than thru wood.