what's the appeal of pyro? I've never used it...
I've never used pyrogallol so cant comment there, I I have used most of the commercially available pyrocatechol developers (DiXactol. Exactol Lux, Precyscol an Pyrocat HD). I've now settled on homebrewed Pyrocat HD as my standard.
What's the appeal? well, where do I start? Many of the claims for these developers seems to be the stuff of snake-oil trickery, excellent compensation from the tan and stain, scalpel like edge effects, very fine grain due to the stain mask, amazingly smooth and delicate highlight tones/ seperation, full or close to full film speed; but they are all true in my book. Negs from catechol are very easy to print, they look brown,thin and wafty, but dont be fooled, they work like a dream. Is that enough? And, if you mix it yourself, the cost is extremely low indeed (as compared to the commercial available preparations).