I would like to open this question again because MF really depends on DPS and it is not fair for all support classes.
I know somebody, who has a warrior with over 150 MF and finds a lot of exo items and another my friends plays with a necro (support), also over 150 MF, and finds just green and blue items, sometimes yellow and once per month or two, one exo item.
So Anet, please change it so it is fair to everybody. Not just somebody.
So I have a Warrior who has over 150 MF and an Ele support friend who also have over 150 MF. Both of them have been getting exotics every now and then. So i guess that is enough to justify something.