Don't bother.

I thought boosting in ZG might be fun because it would be another outdoor zone I could pull with my mount. Well the grey mobs manage to chain stun my 80 DK. While they never killed me it took so damn long to kill a group of mobs it was just not worth it. By the time I got to the first boss mob I was over 1 hour in the dungeon.

So I went to Hellfire Ramparts instead and it is ZOMG awesome 2k a kill at level 55 made 1.2 levels on one full clear took me about 30 minutes. The only real trick to the ramparts is keeping aggro on the casters. Since I am boosting a shaman/druid I use them for heals so I can pull bigger groups.

Ramparts is definatly the way to go 55 to 60.

Not sure after 60 I may use the Zygor Add on or just keep boosting.