I don't know too much about a lock (i have one, but was scared to use him for grinding), but 15 min per cath clear is real nice. It took me 22 minutes for my rogue to do. I would say do ZF till 45 (takes my rogue about 55 minutes to do a clear, i skip the stairs because i have no aoe to kill them, but i do the zombie trolls where you have to click on the graves). I say i get about 5 to 6 bars there. Right now i am doing scholo (can start at 45) i get about 2.5 bars there only clearing the first room, which takes me 15 minutes. My plan was to do the first 3 rooms but 1 mob run from group to group which agros the whole room and they summon skeletons. After 10 seconds i had the whole room on me and 30 skeletons. Thank god for vanish.