as i'm sure you know, 75% of a paint job is the prep work, 25% is slapping paint on the walls.

my opinion.....i would advise against using a sprayer inside a house that you're living in. you would basically have to remove all the furniture and everything else from the room, cover the floors, tape off the windows and lighting fixtures and then after you spray, you'll have to go over some, most or all of the surfaces with a roller. you can spray a whole room in 10 minutes but there's alot that goes along with it and i don't think it's worth the time for prep and the mess you could make.

general rule of thumb for any given room

1 ceiling
2 trim
3 walls
4 anything else such as cabinets or book cases

if you want to cut a little time you can use an 18" roller instead of a 9" but that's still not going to make a very big difference if you're just going room to room. it's an unusual sight to see painters spray inside a house unless it's new construction and they can run from room to room easily.