ISFD vs Separated Backup Indicators

[PlainandSimplePaints 45]

Whats really the pros of the ISFD? I know on the 737 there is many reasons. I have seen many pilots say the prefer the separated ones because the info is split into three gauges not one.

[JWNoctis 4]

ISFD allows fail operational autoland for it's another...inertial reference unit? And it saves weight and reduces parts count, though that's bean counter's concern.

 

EDIT: Oops, thought you meant the 737! Guess I need to go check some docs now.

 

EDIT2: Only difference seemed to be the source of attitude data. Secondary attitude and air data reference unit is the only source of attitude data for non-ISFD attitude indicator, while ISFD had internal inertial sensors. The parts count and weight reduction part still stands.