I mixed a batch of Q-P-TEA as per Patrick's formula (10g Hydroquinone, 0.2g Phenidone, 100ml TEA) and tried it on a roll of Tri-X. To be on the safe side I used a 1+30 dilution and developed the roll for 17.5 minutes at 21°C. The negatives do have a brown stain that looks rather prominent to me but then I can't compare it to negs developed with Pyro or Catechol. Grain is reduced, the negatives are sharp and do print well on grade 2.
Does anybody have dilutions/times to compare? HP5+ anyone?