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For me there is just no point doing less then 2 runs but 3 often even its out.
Standard mobs WL = 1 run ~325 mob
Prot = 420 mobs
bump it up
why would you want a high tiered low level item anyway? the break rate it far too high to be worth it :/ it starts getting useful around lvl 25-40 ...
An old discussion on convergence.
(the link points to somewhere in the middle of it where there are most wise thoughts and charts )