A5S is easier than A1S and level of Turn 6 release.
A6S wasn't THAT hard, it was just Blaster being a RNG god. 1 mine that almost 1 shots a tank at low Ilvls and have to grab 2, and the Mirages 1 shot anyone except Tanks if you screwed up. 2 mines screwed Mirage baiting positional.
Brute Justice is difficult, but it doesn't come close to A3S.