So are they good?
Yes but only in some areas among the very best
If you get offered a role with them should you take it?
a) which other offers you have
b) what kind of work you would like to do – ATK will offer you more operations- projects (procurement, manufacturing, supply chain management) and less pure strategy work
(By the way I didn't)
Could it be MBBBA?
No – the third B (BAH) is already questionable – ATK is for sure a good company, but not on level with McK and BCG (as are Oliver Wyman, ADL, Monitor, Roland Berger, OC&C)