Both PMK and ABC and BPF really work well together. If you're going to enlarge that 120 negative, I suggest PMK because BPF is pretty grainy all by itself, and the grain is made even more evident by a pyro developer.
You'll be very happy with the results. One thing...be SURE to use distilled water with in the pyro developer because if you're not careful the BPF film base stains significantly. I find the more distilled water I use in the process, the clearer the film base.
It's great stuff. Have fun!