I've been grinding outlands rep as an 80 spreist and here's what I've found
In 1 hour I can grind 160 Zaxxis Insignia and about 10 prison keys.
That works out to roughly 4k Rep from insignia and 2.5k from keys (assuming each gives 250 which they don't always) - so call it 6K per hour from the area just south of Area 52 (i'm ignoring the random 500 rep you can get from some prisoners)
if I grind warbeads from Laughing skull ruins and the cave just north of Halaa then in 1 hour I can grind about 70 beads from 200 ogre kills.
Remember that beads are worth 500 Maghar Rep or 250 Consortium so this hour would get 2K from kills and 3.5k from beads on Maghar/1.75k on Consortium
Insignia = 6k/hr
Maghar beads = 5.5k/hr
Consortium beads = 3.75k/hr (2k mag 1.75k consort)
Bottom line? So if you are grinding BOTH reputations then save the beads for Maghar don't hand them in for Consortium and grind insignia in Netherstorm, it'll save you about 1/3 of your time.
If you're grinding Maghar then don't bother with insignia (duh), if you're grinding Consortium then go straight to Netherstorm
DrKazza