Well, I actually went through and did a complete, controlled test, and boy was I surprised..
My findings are (and I have repeated these, but please someone else do this as well).
I have latest firmware, apps etc.
Exposure metadata are recorded the same during aeb both for raw and jpeg. Same exposure-settings (aperture/shutter/iso) but with a added Exposure Bias for each shot. These are consistent and correct.
A-mode ISO 100: aeb almost works, that is 4 out of the 5 shots have the correct exposure with consistent noise. The exception is + 2/3 and + 1 1/3 which are the same. We end up with four out of 5 different exposures. (this is not a problem for aeb with 3 shots)
A-mode ISO 400: aeb works, that is 5 out of the 5 shots have the correct exposure with consistent noise.
M-mode ISO 100: exposure values are different on all shots, but the noise varies horribly. Not sure what is going on here. Further, both +2/3 and +1 1/3 exposure are darker than reference?
M-mode ISO 400: exposure values are different on all shots, but again the noise varies horribly. The same exposure for ISO 100 might actually be worse than 400 (??)
I have added a comparison for same exposure values (subjectively) for manual and aperture at iso 100
For shutter priority, all shots come out the same (so not working at all).
Conclusion: AE 3 shots seems to work for A mode. 5 shots works in some cases. M mode wildly inconsistent and unusable. S mode unusable
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