My scratch mix tanning developers have all been based on pyrogallol. This has been very limited to some P-TEA, 110 and 550 Pyro, Koch's experiments and a few things of my own. I only recently added catechol to my chem shelf. Some experiences awhile back with diXactol and WD2D+ (which I believe are catechol based) seemed to be more compatible with my general use of VC papers. How interchangeable are these two developing agents? What are their general energy/tanning levels in relation to each other? I've come to enjoy the ease of use of glycol and TEA based concentrates. Are there issues related to these compatabilities that I should be aware of with the catechol? I've got some things working quite well but think I would like the less-green tones that the catechol based concoctions seem to produce.