Which Wrath of the Lich King dungeon will provide the highest rep/hour?

I'm farming out my LK reps (going for Beloved title, 36/70!) and I have 4 reps in LK that can be farmed with the help of a tabard.

Very soon (my guild only needs a leatherworker) I'll have access to the banner which will double my rep gains. Now this has a 10 minute CD, so I'd like to maximize that if possible.

Which dungeon will allow me to farm repeatedly and gain reputation with the tabards with the highest reputation velocity? If two of them are rather close in their xp gain, but one is linear and the other circles around, then clearly the latter would be better because I would be in range of the banner more often.

And no, this isn't on my level 1 this time. :-)