Forgot one thing ... PMK might not be your best choice for long stand dev either. Although the A&B concentrates seem to last forever, once
mixed, you need to use the developer immediately, and it might not stay predictable for as long as half an hour. Fifteen minutes certainly.
As someone who uses PMK Pyro all the time for 30 minutes, semi-stand, I recommend it. It works beautifully. Just don't try to reuse it. One use only.