I voted get the job done, because i, myself like to get things done because i'm pretty strict with how much time i allow myself to play on a non raid night. And a quick random is my preference, but saying that i have in the past helped random people with there quests in ICC and have often started FoS and moved on to HoR with the same group just so they can do there quest.
Depends on my mood but i prefer to do it quick, i deffinately have not got a god complex but i've had the comfort of tackling this game from most aspects (Range, Melee, tank and Healer).