AJFA versus AMOLAD is rough because I treasure both albums. One is classic and the other is probably Maiden's most consistent album. It's been said by others, but I don't love the lack of bass on AJFA (as a bass player myself), although the songs are all killer. There's not a filler track on there, which is the same as AMOLAD, honestly. But AJFA is just so classic, so Metallica gets my vote.
This Priest album isn't really up my alley, but I'll never vote for Queensryche. I'm really sick of all this Priest at this point, but oh well.
Neither this Metallica album nor this Maiden album are my favorites by them, and they each have about the same quality of great tracks versus filler. But in Metallica's case, those great tracks are iconic, whereas with Maiden the only tracks I really love are Empire and the title track (Red and Black is solid, too, but not great). For Whom the Bell Tolls, Fade to Black, Creeping Death, and Call of Ktulu are all excellent. Metallica.
Anthrax does very little for me. Even when they had John Bush (who I greatly preferred to their original singer), they just sounded like a watered-down Armored Saint to me. SIT is far from my favorite Maiden album, but it does have a few killer tracks. Maiden, easily.