Just to clarify from a personal point of view I've only carried out a visual comparison with Peter Hogan's alkaline and Fotospeed's acid fixers with 4x5 T-max 100 developed in PMK pyro and I could not see a visual difference as to the amount of stain. They looked the same to me.
Originally Posted by pentaxuser
While I have used Peter's excellent Prescysol developer I have never done a comparison with this developer. Peter clearly states on his website that his alkaline fixer preserves the staining effect.
The effect may indeed be apparent with different films/developers it would be nice if someone could carry out a comprehensive test with various films/staining developers.