you lose more dps from wearing mana drain instead of hp drain / pure dmg adorns on weaps, as if you do using mb for a short time. swap when hemo begins to tick to shorten the loss also. just a few dps but as often said, it adds all up
if youre in an casual guild, youll do probably better with one or two mana drains cause fights take much longer. i used to use one of them before i joined fable. it helped. however, now i got the mana drain on a 3rd weap that i just euip when mana needed but didnt use it by now so cant tell how much it affects our dps. shoudl be a very low value tho if that weap is equal to your usual ones.