I've tried quite a few pyro options, and have even cooked up a couple of tweaks of my own; but my standby is PMK from pyrogallol, with its yellow-green stain. Very little difference in practical VC application from brown-green Pyrocat stain, including split printing. The grain comes out a little smoother with certain films than with Pyrocat. FP4 results will be similar. PMK is a great developer in terms of shelf life of the two concentrates, tray usage, and hand inversion drum usage. I don't recommend it for aggressive rotary drum processing.