FX-15, Acutol, Acutol-S.... Help!

Could anyone clear up what's up with these 3, comparison-wise? I've snooped around the net and all I've found is other people asking the same thing. I mixed a test batch of FX-15 and found that it was much more active than the Acutol data would indicate and I know that FX-15 is mentioned as Acutol-S. The Acutol data at Paterson and on Massive Dev Chart show different dilutions, etc than the FX-15 info seems to indicate. Does anyone have any experience with this?

Hi Craig,

I like this developer a lot . In particular, it works better with Fuji 400 than any other developer I have tried, and I have tried plenty. Its activity diluted 1:3 is midway between D76 1:3 and Microphen 1:3, so for any film where times are available for these developers you should get good negatives using the FX 15 at 1:3 with a time half way between them and with 4 gentle inversions per minute.

Acutol S and FX15 are, to the best of my knowledge, identical.
Good Luck!

Jay L