nitpicker330
The stby AI's do NOT lag in the turns, have you heard of roll precession? Because the A/C turns at a gentle AOB in the cruise, below the roll precession cutoff limit, the stby AI will precess in the turn. It will show a minor bank on roll out but will quickly re-erect on wings level.
The DDRMI has been taken away as it was just a repeater of either ADIRU 1 or 3 so not independent, whereas the "E2B"is independent.