you can see in the formula that it is pretty basic stuff. But it has a sparkle that I don't get with other developers. I have been shooting a series of still life photos for a few weeks and was using Rodinal and though I love Rodinal I couldn't get the kind of "snap" I wanted.. contrast I guess. I don't plot curves but I would guess this one has a pretty steep shoulder. The exposures I have been doing are complicated with bellows extension and multiple flash, so I can't comment on film speed.